FMC_BCR1 (BCR1)

FMC_BCR3 (BCR3)

FMC_BWTR1 (BWTR1)

FMC_BWTR2 (BWTR2)

FMC_BWTR3 (BWTR3)

FMC_BWTR4 (BWTR4)

FMC_BTR3 (BTR3)

FMC_BCR4 (BCR4)

FMC_BTR4 (BTR4)

FMC_PCSCNTR (PCSCNTR)

FMC_CSQCR (CSQCR)

FMC_CSQCFGR1 (CSQCFGR1)

FMC_CSQCFGR2 (CSQCFGR2)

FMC_CSQCFGR3 (CSQCFGR3)

FMC_CSQAR1 (CSQAR1)

FMC_CSQAR2 (CSQAR2)

FMC_CSQIER (CSQIER)

FMC_CSQISR (CSQISR)

FMC_CSQICR (CSQICR)

FMC_CSQEMSR (CSQEMSR)

FMC_BCHIER (BCHIER)

FMC_BCHISR (BCHISR)

FMC_BCHICR (BCHICR)

FMC_BCHPBR1 (BCHPBR1)

FMC_BCHPBR2 (BCHPBR2)

FMC_BCHPBR3 (BCHPBR3)

FMC_BCHPBR4 (BCHPBR4)

FMC_BCHDSR0 (BCHDSR0)

FMC_BCHDSR1 (BCHDSR1)

FMC_BCHDSR2 (BCHDSR2)

FMC_BCHDSR3 (BCHDSR3)

FMC_BCHDSR4 (BCHDSR4)

FMC_HWCFGR2 (HWCFGR2)

FMC_HWCFGR1 (HWCFGR1)

FMC_VERR (VERR)

FMC_IDR (IDR)

FMC_SIDR (SIDR)

FMC_BTR1 (BTR1)

FMC_BCR2 (BCR2)

FMC_PCR (PCR)

FMC_SR (SR)

FMC_PMEM (PMEM)

FMC_PATT (PATT)

FMC_HPR (HPR)

FMC_HECCR (HECCR)

FMC_BTR2 (BTR2)

MBKEN : Memory bank enable bit This bit enables the memory bank. After reset Bank1 is enabled, all others are disabled. Accessing a disabled bank causes an ERROR on AXI bus.
bits : 0 - 0 (1 bit)

MUXEN : Address/data multiplexing enable bit When this bit is set, the address and data values are multiplexed on the data bus, valid only with NOR and PSRAM memories:
bits : 1 - 1 (1 bit)

MTYP : Memory type These bits define the type of external memory attached to the corresponding memory bank:
bits : 2 - 3 (2 bit)

MWID : Memory data bus width Defines the external memory device width, valid for all type of memories.
bits : 4 - 5 (2 bit)

FACCEN : Flash access enable This bit enables NOR Flash memory access operations.
bits : 6 - 6 (1 bit)

BURSTEN : Burst enable bit This bit enables/disables synchronous accesses during read operations. It is valid only for synchronous memories operating in Burst mode:
bits : 8 - 8 (1 bit)

WAITPOL : Wait signal polarity bit This bit defines the polarity of the wait signal from memory used for either in synchronous or asynchronous mode:
bits : 9 - 9 (1 bit)

WAITCFG : Wait timing configuration The NWAIT signal indicates whether the data from the memory are valid or if a wait state must be inserted when accessing the memory in synchronous mode. This configuration bit determines if NWAIT is asserted by the memory one clock cycle before the wait state or during the wait state:
bits : 11 - 11 (1 bit)

WREN : Write enable bit This bit indicates whether write operations are enabled/disabled in the bank by the FMC:
bits : 12 - 12 (1 bit)

WAITEN : Wait enable bit This bit enables/disables wait-state insertion via the NWAIT signal when accessing the memory in synchronous mode.
bits : 13 - 13 (1 bit)

EXTMOD : Extended mode enable. This bit enables the FMC to program the write timings for asynchronous accesses inside the FMC_BWTR register, thus resulting in different timings for read and write operations. Note: When the extended mode is disabled, the FMC can operate in Mode1 or Mode2 as follows: ** Mode 1 is the default mode when the SRAM/PSRAM memory type is selected (MTYP =0x0 or 0x01) ** Mode 2 is the default mode when the NOR memory type is selected (MTYP = 0x10).
bits : 14 - 14 (1 bit)

ASYNCWAIT : Wait signal during asynchronous transfers This bit enables/disables the FMC to use the wait signal even during an asynchronous protocol.
bits : 15 - 15 (1 bit)

CPSIZE : CRAM Page Size These are used for Cellular RAM 1.5 which does not allow burst access to cross the address boundaries between pages. When these bits are configured, the FMC controller splits automatically the burst access when the memory page size is reached (refer to memory datasheet for page size). Other configuration: reserved.
bits : 16 - 18 (3 bit)

CBURSTRW : Write burst enable For PSRAM (CRAM) operating in Burst mode, the bit enables synchronous accesses during write operations. The enable bit for synchronous read accesses is the BURSTEN bit in the FMC_BCRx register.
bits : 19 - 19 (1 bit)

CCLKEN : Continuous Clock Enable This bit enables the FMC_CLK clock output to external memory devices. Note: The CCLKEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register. Bank 1 must be configured in synchronous mode to generate the FMC_CLK continuous clock. If CCLKEN bit is set, the FMC_CLK clock ratio is specified by CLKDIV value in the FMC_BTR1 register. CLKDIV in FMC_BWTR1 is dont care. If the synchronous mode is used and CCLKEN bit is set, the synchronous memories connected to other banks than Bank 1 are clocked by the same clock (the CLKDIV value in the FMC_BTR2..4 and FMC_BWTR2..4 registers for other banks has no effect.)
bits : 20 - 20 (1 bit)

NBLSET : NBLSET
bits : 22 - 23 (2 bit)

FMCEN : FMC controller Enable This bit enables/disables the FMC controller. Note: The FMCEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register.
bits : 31 - 31 (1 bit)

MBKEN : Memory bank enable bit This bit enables the memory bank. After reset Bank1 is enabled, all others are disabled. Accessing a disabled bank causes an ERROR on AXI bus.
bits : 0 - 0 (1 bit)

MUXEN : Address/data multiplexing enable bit When this bit is set, the address and data values are multiplexed on the data bus, valid only with NOR and PSRAM memories:
bits : 1 - 1 (1 bit)

MTYP : Memory type These bits define the type of external memory attached to the corresponding memory bank:
bits : 2 - 3 (2 bit)

MWID : Memory data bus width Defines the external memory device width, valid for all type of memories.
bits : 4 - 5 (2 bit)

FACCEN : Flash access enable This bit enables NOR Flash memory access operations.
bits : 6 - 6 (1 bit)

BURSTEN : Burst enable bit This bit enables/disables synchronous accesses during read operations. It is valid only for synchronous memories operating in Burst mode:
bits : 8 - 8 (1 bit)

WAITPOL : Wait signal polarity bit This bit defines the polarity of the wait signal from memory used for either in synchronous or asynchronous mode:
bits : 9 - 9 (1 bit)

WAITCFG : Wait timing configuration The NWAIT signal indicates whether the data from the memory are valid or if a wait state must be inserted when accessing the memory in synchronous mode. This configuration bit determines if NWAIT is asserted by the memory one clock cycle before the wait state or during the wait state:
bits : 11 - 11 (1 bit)

WREN : Write enable bit This bit indicates whether write operations are enabled/disabled in the bank by the FMC:
bits : 12 - 12 (1 bit)

WAITEN : Wait enable bit This bit enables/disables wait-state insertion via the NWAIT signal when accessing the memory in synchronous mode.
bits : 13 - 13 (1 bit)

EXTMOD : Extended mode enable. This bit enables the FMC to program the write timings for asynchronous accesses inside the FMC_BWTR register, thus resulting in different timings for read and write operations. Note: When the extended mode is disabled, the FMC can operate in Mode1 or Mode2 as follows: ** Mode 1 is the default mode when the SRAM/PSRAM memory type is selected (MTYP =0x0 or 0x01) ** Mode 2 is the default mode when the NOR memory type is selected (MTYP = 0x10).
bits : 14 - 14 (1 bit)

ASYNCWAIT : Wait signal during asynchronous transfers This bit enables/disables the FMC to use the wait signal even during an asynchronous protocol.
bits : 15 - 15 (1 bit)

CPSIZE : CRAM Page Size These are used for Cellular RAM 1.5 which does not allow burst access to cross the address boundaries between pages. When these bits are configured, the FMC controller splits automatically the burst access when the memory page size is reached (refer to memory datasheet for page size). Other configuration: reserved.
bits : 16 - 18 (3 bit)

CBURSTRW : Write burst enable For PSRAM (CRAM) operating in Burst mode, the bit enables synchronous accesses during write operations. The enable bit for synchronous read accesses is the BURSTEN bit in the FMC_BCRx register.
bits : 19 - 19 (1 bit)

CCLKEN : Continuous Clock Enable This bit enables the FMC_CLK clock output to external memory devices. Note: The CCLKEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register. Bank 1 must be configured in synchronous mode to generate the FMC_CLK continuous clock. If CCLKEN bit is set, the FMC_CLK clock ratio is specified by CLKDIV value in the FMC_BTR1 register. CLKDIV in FMC_BWTR1 is dont care. If the synchronous mode is used and CCLKEN bit is set, the synchronous memories connected to other banks than Bank 1 are clocked by the same clock (the CLKDIV value in the FMC_BTR2..4 and FMC_BWTR2..4 registers for other banks has no effect.)
bits : 20 - 20 (1 bit)

NBLSET : NBLSET
bits : 22 - 23 (2 bit)

FMCEN : FMC controller Enable This bit enables/disables the FMC controller. Note: The FMCEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register.
bits : 31 - 31 (1 bit)

ADDSET : Address setup phase duration. These bits are written by software to define the duration of the address setup phase in KCK_FMC cycles (refer to Figure81 to Figure93), used in asynchronous accesses: ... Note: In synchronous accesses, this value is not used, the address setup phase is always 1 Flash clock period duration. In muxed mode, the minimum ADDSET value is 1.
bits : 0 - 3 (4 bit)

ADDHLD : Address-hold phase duration. These bits are written by software to define the duration of the address hold phase (refer to Figure81 to Figure93), used in asynchronous multiplexed accesses: ... Note: In synchronous NOR Flash accesses, this value is not used, the address hold phase is always 1 Flash clock period duration.
bits : 4 - 7 (4 bit)

DATAST : Data-phase duration. These bits are written by software to define the duration of the data phase (refer to Figure81 to Figure93), used in asynchronous SRAM, PSRAM and NOR Flash memory accesses:
bits : 8 - 15 (8 bit)

BUSTURN : Bus turnaround phase duration These bits are written by software to add a delay at the end of a write transaction to match the minimum time between consecutive transactions (tEHEL from ENx high to ENx low): (BUSTRUN + 1) KCK_FMC period ≥ tEHELmin. The programmed bus turnaround delay is inserted between a an asynchronous write transfer and any other asynchronous /synchronous read or write transfer to or from a static bank. If a read operation is performed, the bank can be the same or a different one, whereas it must be different in case of write operation to the bank, except in muxed mode or mode D. In some cases, whatever the programmed BUSTRUN values, the bus turnaround delay is fixed as follows: The bus turnaround delay is not inserted between two consecutive asynchronous write transfers to the same static memory bank except for muxed mode and mode D. There is a bus turnaround delay of 2 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to the same bank A synchronous write transfer ((in Burst or Single mode) and an asynchronous write or read transfer to or from static memory bank. There is a bus turnaround delay of 3 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to different static banks. A synchronous write transfer (in Burst or Single mode) and a synchronous read from the same or a different bank. ...
bits : 16 - 19 (4 bit)

ACCMOD : Access mode. These bits specify the asynchronous access modes as shown in the next timing diagrams.These bits are taken into account only when the EXTMOD bit in the FMC_BCRx register is 1.
bits : 28 - 29 (2 bit)

DATAHLD : DATAHLD
bits : 30 - 31 (2 bit)

ADDSET : Address setup phase duration. These bits are written by software to define the duration of the address setup phase in KCK_FMC cycles (refer to Figure81 to Figure93), used in asynchronous accesses: ... Note: In synchronous accesses, this value is not used, the address setup phase is always 1 Flash clock period duration. In muxed mode, the minimum ADDSET value is 1.
bits : 0 - 3 (4 bit)

ADDHLD : Address-hold phase duration. These bits are written by software to define the duration of the address hold phase (refer to Figure81 to Figure93), used in asynchronous multiplexed accesses: ... Note: In synchronous NOR Flash accesses, this value is not used, the address hold phase is always 1 Flash clock period duration.
bits : 4 - 7 (4 bit)

DATAST : Data-phase duration. These bits are written by software to define the duration of the data phase (refer to Figure81 to Figure93), used in asynchronous SRAM, PSRAM and NOR Flash memory accesses:
bits : 8 - 15 (8 bit)

BUSTURN : Bus turnaround phase duration These bits are written by software to add a delay at the end of a write transaction to match the minimum time between consecutive transactions (tEHEL from ENx high to ENx low): (BUSTRUN + 1) KCK_FMC period ≥ tEHELmin. The programmed bus turnaround delay is inserted between a an asynchronous write transfer and any other asynchronous /synchronous read or write transfer to or from a static bank. If a read operation is performed, the bank can be the same or a different one, whereas it must be different in case of write operation to the bank, except in muxed mode or mode D. In some cases, whatever the programmed BUSTRUN values, the bus turnaround delay is fixed as follows: The bus turnaround delay is not inserted between two consecutive asynchronous write transfers to the same static memory bank except for muxed mode and mode D. There is a bus turnaround delay of 2 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to the same bank A synchronous write transfer ((in Burst or Single mode) and an asynchronous write or read transfer to or from static memory bank. There is a bus turnaround delay of 3 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to different static banks. A synchronous write transfer (in Burst or Single mode) and a synchronous read from the same or a different bank. ...
bits : 16 - 19 (4 bit)

ACCMOD : Access mode. These bits specify the asynchronous access modes as shown in the next timing diagrams.These bits are taken into account only when the EXTMOD bit in the FMC_BCRx register is 1.
bits : 28 - 29 (2 bit)

DATAHLD : DATAHLD
bits : 30 - 31 (2 bit)

ADDSET : Address setup phase duration. These bits are written by software to define the duration of the address setup phase in KCK_FMC cycles (refer to Figure81 to Figure93), used in asynchronous accesses: ... Note: In synchronous accesses, this value is not used, the address setup phase is always 1 Flash clock period duration. In muxed mode, the minimum ADDSET value is 1.
bits : 0 - 3 (4 bit)

ADDHLD : Address-hold phase duration. These bits are written by software to define the duration of the address hold phase (refer to Figure81 to Figure93), used in asynchronous multiplexed accesses: ... Note: In synchronous NOR Flash accesses, this value is not used, the address hold phase is always 1 Flash clock period duration.
bits : 4 - 7 (4 bit)

DATAST : Data-phase duration. These bits are written by software to define the duration of the data phase (refer to Figure81 to Figure93), used in asynchronous SRAM, PSRAM and NOR Flash memory accesses:
bits : 8 - 15 (8 bit)

BUSTURN : Bus turnaround phase duration These bits are written by software to add a delay at the end of a write transaction to match the minimum time between consecutive transactions (tEHEL from ENx high to ENx low): (BUSTRUN + 1) KCK_FMC period ≥ tEHELmin. The programmed bus turnaround delay is inserted between a an asynchronous write transfer and any other asynchronous /synchronous read or write transfer to or from a static bank. If a read operation is performed, the bank can be the same or a different one, whereas it must be different in case of write operation to the bank, except in muxed mode or mode D. In some cases, whatever the programmed BUSTRUN values, the bus turnaround delay is fixed as follows: The bus turnaround delay is not inserted between two consecutive asynchronous write transfers to the same static memory bank except for muxed mode and mode D. There is a bus turnaround delay of 2 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to the same bank A synchronous write transfer ((in Burst or Single mode) and an asynchronous write or read transfer to or from static memory bank. There is a bus turnaround delay of 3 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to different static banks. A synchronous write transfer (in Burst or Single mode) and a synchronous read from the same or a different bank. ...
bits : 16 - 19 (4 bit)

ACCMOD : Access mode. These bits specify the asynchronous access modes as shown in the next timing diagrams.These bits are taken into account only when the EXTMOD bit in the FMC_BCRx register is 1.
bits : 28 - 29 (2 bit)

DATAHLD : DATAHLD
bits : 30 - 31 (2 bit)

ADDSET : Address setup phase duration. These bits are written by software to define the duration of the address setup phase in KCK_FMC cycles (refer to Figure81 to Figure93), used in asynchronous accesses: ... Note: In synchronous accesses, this value is not used, the address setup phase is always 1 Flash clock period duration. In muxed mode, the minimum ADDSET value is 1.
bits : 0 - 3 (4 bit)

ADDHLD : Address-hold phase duration. These bits are written by software to define the duration of the address hold phase (refer to Figure81 to Figure93), used in asynchronous multiplexed accesses: ... Note: In synchronous NOR Flash accesses, this value is not used, the address hold phase is always 1 Flash clock period duration.
bits : 4 - 7 (4 bit)

DATAST : Data-phase duration. These bits are written by software to define the duration of the data phase (refer to Figure81 to Figure93), used in asynchronous SRAM, PSRAM and NOR Flash memory accesses:
bits : 8 - 15 (8 bit)

BUSTURN : Bus turnaround phase duration These bits are written by software to add a delay at the end of a write transaction to match the minimum time between consecutive transactions (tEHEL from ENx high to ENx low): (BUSTRUN + 1) KCK_FMC period ≥ tEHELmin. The programmed bus turnaround delay is inserted between a an asynchronous write transfer and any other asynchronous /synchronous read or write transfer to or from a static bank. If a read operation is performed, the bank can be the same or a different one, whereas it must be different in case of write operation to the bank, except in muxed mode or mode D. In some cases, whatever the programmed BUSTRUN values, the bus turnaround delay is fixed as follows: The bus turnaround delay is not inserted between two consecutive asynchronous write transfers to the same static memory bank except for muxed mode and mode D. There is a bus turnaround delay of 2 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to the same bank A synchronous write transfer ((in Burst or Single mode) and an asynchronous write or read transfer to or from static memory bank. There is a bus turnaround delay of 3 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to different static banks. A synchronous write transfer (in Burst or Single mode) and a synchronous read from the same or a different bank. ...
bits : 16 - 19 (4 bit)

ACCMOD : Access mode. These bits specify the asynchronous access modes as shown in the next timing diagrams.These bits are taken into account only when the EXTMOD bit in the FMC_BCRx register is 1.
bits : 28 - 29 (2 bit)

DATAHLD : DATAHLD
bits : 30 - 31 (2 bit)

ADDSET : Address setup phase duration These bits are written by software to define the duration of the address setup phase (refer to Figure81 to Figure93), used in SRAMs, ROMs and asynchronous NOR Flash: For each access mode address setup phase duration, please refer to the respective figure (refer to Figure81 to Figure93). Note: In synchronous accesses, this value is dont care. In Muxed mode or Mode D, the minimum value for ADDSET is 1.
bits : 0 - 3 (4 bit)

ADDHLD : Address-hold phase duration These bits are written by software to define the duration of the address hold phase (refer to Figure81 to Figure93), used in mode D or multiplexed accesses: For each access mode address-hold phase duration, please refer to the respective figure (Figure81 to Figure93). Note: In synchronous accesses, this value is not used, the address hold phase is always 1 memory clock period duration.
bits : 4 - 7 (4 bit)

DATAST : Data-phase duration These bits are written by software to define the duration of the data phase (refer to Figure81 to Figure93), used in asynchronous accesses: For each memory type and access mode data-phase duration, please refer to the respective figure (Figure81 to Figure93). Example: Mode1, write access, DATAST=1: Data-phase duration= DATAST+1 = 2 KCK_FMC clock cycles. Note: In synchronous accesses, this value is dont care.
bits : 8 - 15 (8 bit)

BUSTURN : Bus turnaround phase duration These bits are written by software to add a delay at the end of a write-to-read or read-to write transaction. The programmed bus turnaround delay is inserted between an asynchronous read (in muxed or mode D) or write transaction and any other asynchronous /synchronous read/write from/to a static bank. If a read operation is performed, the bank can be the same or a different one, whereas it must be different in case of write operation to the bank, except in muxed mode or mode D. In some cases, whatever the programmed BUSTRUN values, the bus turnaround delay is fixed as follows: The bus turnaround delay is not inserted between two consecutive asynchronous write transfers to the same static memory bank except in muxed mode and mode D. There is a bus turnaround delay of 1 FMC clock cycle between: Two consecutive asynchronous read transfers to the same static memory bank except for modes muxed and D. An asynchronous read to an asynchronous or synchronous write to any static bank or dynamic bank except in modes muxed and D mode. There is a bus turnaround delay of 2 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to the same bank. A synchronous write (burst or single) access and an asynchronous write or read transfer to or from static memory bank (the bank can be the same or a different one in case of a read operation. Two consecutive synchronous read operations (in Burst or Single mode) followed by any synchronous/asynchronous read or write from/to another static memory bank. There is a bus turnaround delay of 3 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to different static banks. A synchronous write access (in Burst or Single mode) and a synchronous read from the same or a different bank. The bus turnaround delay allows to match the minimum time between consecutive transactions (tEHEL from NEx high to NEx low) and the maximum time required by the memory to free the data bus after a read access (tEHQZ): (BUSTRUN + 1) KCK_FMC period ≥ tEHELmin and (BUSTRUN + 2)KCK_FMC period ≥ tEHQZmax if EXTMOD = 0 (BUSTRUN + 2)KCK_FMC period ≥ max (tEHELmin, tEHQZmax) if EXTMOD =1. ...
bits : 16 - 19 (4 bit)

CLKDIV : Clock divide ratio (for FMC_CLK signal) These bits define the period of FMC_CLK clock output signal, expressed in number of KCK_FMC cycles: In asynchronous NOR Flash, SRAM or PSRAM accesses, this value is dont care. Note: Refer to Section20.6.5: Synchronous transactions for FMC_CLK divider ratio formula)
bits : 20 - 23 (4 bit)

DATLAT : Data latency for synchronous memory For synchronous access with read write burst mode enabled these bits define the number of memory clock cycles
bits : 24 - 27 (4 bit)

ACCMOD : Access mode These bits specify the asynchronous access modes as shown in the timing diagrams. They are taken into account only when the EXTMOD bit in the FMC_BCRx register is 1.
bits : 28 - 29 (2 bit)

DATAHLD : DATAHLD
bits : 30 - 31 (2 bit)

MBKEN : Memory bank enable bit This bit enables the memory bank. After reset Bank1 is enabled, all others are disabled. Accessing a disabled bank causes an ERROR on AXI bus.
bits : 0 - 0 (1 bit)

MUXEN : Address/data multiplexing enable bit When this bit is set, the address and data values are multiplexed on the data bus, valid only with NOR and PSRAM memories:
bits : 1 - 1 (1 bit)

MTYP : Memory type These bits define the type of external memory attached to the corresponding memory bank:
bits : 2 - 3 (2 bit)

MWID : Memory data bus width Defines the external memory device width, valid for all type of memories.
bits : 4 - 5 (2 bit)

FACCEN : Flash access enable This bit enables NOR Flash memory access operations.
bits : 6 - 6 (1 bit)

BURSTEN : Burst enable bit This bit enables/disables synchronous accesses during read operations. It is valid only for synchronous memories operating in Burst mode:
bits : 8 - 8 (1 bit)

WAITPOL : Wait signal polarity bit This bit defines the polarity of the wait signal from memory used for either in synchronous or asynchronous mode:
bits : 9 - 9 (1 bit)

WAITCFG : Wait timing configuration The NWAIT signal indicates whether the data from the memory are valid or if a wait state must be inserted when accessing the memory in synchronous mode. This configuration bit determines if NWAIT is asserted by the memory one clock cycle before the wait state or during the wait state:
bits : 11 - 11 (1 bit)

WREN : Write enable bit This bit indicates whether write operations are enabled/disabled in the bank by the FMC:
bits : 12 - 12 (1 bit)

WAITEN : Wait enable bit This bit enables/disables wait-state insertion via the NWAIT signal when accessing the memory in synchronous mode.
bits : 13 - 13 (1 bit)

EXTMOD : Extended mode enable. This bit enables the FMC to program the write timings for asynchronous accesses inside the FMC_BWTR register, thus resulting in different timings for read and write operations. Note: When the extended mode is disabled, the FMC can operate in Mode1 or Mode2 as follows: ** Mode 1 is the default mode when the SRAM/PSRAM memory type is selected (MTYP =0x0 or 0x01) ** Mode 2 is the default mode when the NOR memory type is selected (MTYP = 0x10).
bits : 14 - 14 (1 bit)

ASYNCWAIT : Wait signal during asynchronous transfers This bit enables/disables the FMC to use the wait signal even during an asynchronous protocol.
bits : 15 - 15 (1 bit)

CPSIZE : CRAM Page Size These are used for Cellular RAM 1.5 which does not allow burst access to cross the address boundaries between pages. When these bits are configured, the FMC controller splits automatically the burst access when the memory page size is reached (refer to memory datasheet for page size). Other configuration: reserved.
bits : 16 - 18 (3 bit)

CBURSTRW : Write burst enable For PSRAM (CRAM) operating in Burst mode, the bit enables synchronous accesses during write operations. The enable bit for synchronous read accesses is the BURSTEN bit in the FMC_BCRx register.
bits : 19 - 19 (1 bit)

CCLKEN : Continuous Clock Enable This bit enables the FMC_CLK clock output to external memory devices. Note: The CCLKEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register. Bank 1 must be configured in synchronous mode to generate the FMC_CLK continuous clock. If CCLKEN bit is set, the FMC_CLK clock ratio is specified by CLKDIV value in the FMC_BTR1 register. CLKDIV in FMC_BWTR1 is dont care. If the synchronous mode is used and CCLKEN bit is set, the synchronous memories connected to other banks than Bank 1 are clocked by the same clock (the CLKDIV value in the FMC_BTR2..4 and FMC_BWTR2..4 registers for other banks has no effect.)
bits : 20 - 20 (1 bit)

NBLSET : NBLSET
bits : 22 - 23 (2 bit)

FMCEN : FMC controller Enable This bit enables/disables the FMC controller. Note: The FMCEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register.
bits : 31 - 31 (1 bit)

ADDSET : Address setup phase duration These bits are written by software to define the duration of the address setup phase (refer to Figure81 to Figure93), used in SRAMs, ROMs and asynchronous NOR Flash: For each access mode address setup phase duration, please refer to the respective figure (refer to Figure81 to Figure93). Note: In synchronous accesses, this value is dont care. In Muxed mode or Mode D, the minimum value for ADDSET is 1.
bits : 0 - 3 (4 bit)

ADDHLD : Address-hold phase duration These bits are written by software to define the duration of the address hold phase (refer to Figure81 to Figure93), used in mode D or multiplexed accesses: For each access mode address-hold phase duration, please refer to the respective figure (Figure81 to Figure93). Note: In synchronous accesses, this value is not used, the address hold phase is always 1 memory clock period duration.
bits : 4 - 7 (4 bit)

DATAST : Data-phase duration These bits are written by software to define the duration of the data phase (refer to Figure81 to Figure93), used in asynchronous accesses: For each memory type and access mode data-phase duration, please refer to the respective figure (Figure81 to Figure93). Example: Mode1, write access, DATAST=1: Data-phase duration= DATAST+1 = 2 KCK_FMC clock cycles. Note: In synchronous accesses, this value is dont care.
bits : 8 - 15 (8 bit)

BUSTURN : Bus turnaround phase duration These bits are written by software to add a delay at the end of a write-to-read or read-to write transaction. The programmed bus turnaround delay is inserted between an asynchronous read (in muxed or mode D) or write transaction and any other asynchronous /synchronous read/write from/to a static bank. If a read operation is performed, the bank can be the same or a different one, whereas it must be different in case of write operation to the bank, except in muxed mode or mode D. In some cases, whatever the programmed BUSTRUN values, the bus turnaround delay is fixed as follows: The bus turnaround delay is not inserted between two consecutive asynchronous write transfers to the same static memory bank except in muxed mode and mode D. There is a bus turnaround delay of 1 FMC clock cycle between: Two consecutive asynchronous read transfers to the same static memory bank except for modes muxed and D. An asynchronous read to an asynchronous or synchronous write to any static bank or dynamic bank except in modes muxed and D mode. There is a bus turnaround delay of 2 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to the same bank. A synchronous write (burst or single) access and an asynchronous write or read transfer to or from static memory bank (the bank can be the same or a different one in case of a read operation. Two consecutive synchronous read operations (in Burst or Single mode) followed by any synchronous/asynchronous read or write from/to another static memory bank. There is a bus turnaround delay of 3 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to different static banks. A synchronous write access (in Burst or Single mode) and a synchronous read from the same or a different bank. The bus turnaround delay allows to match the minimum time between consecutive transactions (tEHEL from NEx high to NEx low) and the maximum time required by the memory to free the data bus after a read access (tEHQZ): (BUSTRUN + 1) KCK_FMC period ≥ tEHELmin and (BUSTRUN + 2)KCK_FMC period ≥ tEHQZmax if EXTMOD = 0 (BUSTRUN + 2)KCK_FMC period ≥ max (tEHELmin, tEHQZmax) if EXTMOD =1. ...
bits : 16 - 19 (4 bit)

CLKDIV : Clock divide ratio (for FMC_CLK signal) These bits define the period of FMC_CLK clock output signal, expressed in number of KCK_FMC cycles: In asynchronous NOR Flash, SRAM or PSRAM accesses, this value is dont care. Note: Refer to Section20.6.5: Synchronous transactions for FMC_CLK divider ratio formula)
bits : 20 - 23 (4 bit)

DATLAT : Data latency for synchronous memory For synchronous access with read write burst mode enabled these bits define the number of memory clock cycles
bits : 24 - 27 (4 bit)

ACCMOD : Access mode These bits specify the asynchronous access modes as shown in the timing diagrams. They are taken into account only when the EXTMOD bit in the FMC_BCRx register is 1.
bits : 28 - 29 (2 bit)

CSCOUNT : CSCOUNT
bits : 0 - 15 (16 bit)

CNTB1EN : CNTB1EN
bits : 16 - 16 (1 bit)

CNTB2EN : CNTB2EN
bits : 17 - 17 (1 bit)

CNTB3EN : CNTB3EN
bits : 18 - 18 (1 bit)

CNTB4EN : CNTB4EN
bits : 19 - 19 (1 bit)

CSQSTART : CSQSTART
bits : 0 - 0 (1 bit)

CMD2EN : CMD2EN
bits : 1 - 1 (1 bit)

DMADEN : DMADEN
bits : 2 - 2 (1 bit)

ACYNBR : ACYNBR
bits : 4 - 6 (3 bit)

CMD1 : CMD1
bits : 8 - 15 (8 bit)

CMD2 : CMD2
bits : 16 - 23 (8 bit)

CMD1T : CMD1T
bits : 24 - 24 (1 bit)

CMD2T : CMD2T
bits : 25 - 25 (1 bit)

SQSDTEN : SQSDTEN
bits : 0 - 0 (1 bit)

RCMD2EN : RCMD2EN
bits : 1 - 1 (1 bit)

DMASEN : DMASEN
bits : 2 - 2 (1 bit)

RCMD1 : RCMD1
bits : 8 - 15 (8 bit)

RCMD2 : RCMD2
bits : 16 - 23 (8 bit)

RCMD1T : RCMD1T
bits : 24 - 24 (1 bit)

RCMD2T : RCMD2T
bits : 25 - 25 (1 bit)

SNBR : SNBR
bits : 8 - 13 (6 bit)

AC1T : AC1T
bits : 16 - 16 (1 bit)

AC2T : AC2T
bits : 17 - 17 (1 bit)

AC3T : AC3T
bits : 18 - 18 (1 bit)

AC4T : AC4T
bits : 19 - 19 (1 bit)

AC5T : AC5T
bits : 20 - 20 (1 bit)

SDT : SDT
bits : 21 - 21 (1 bit)

RAC1T : RAC1T
bits : 22 - 22 (1 bit)

RAC2T : RAC2T
bits : 23 - 23 (1 bit)

ADDC1 : ADDC1
bits : 0 - 7 (8 bit)

ADDC2 : ADDC2
bits : 8 - 15 (8 bit)

ADDC3 : ADDC3
bits : 16 - 23 (8 bit)

ADDC4 : ADDC4
bits : 24 - 31 (8 bit)

ADDC5 : ADDC5
bits : 0 - 7 (8 bit)

SAO : SAO
bits : 16 - 31 (16 bit)

TCIE : TCIE
bits : 0 - 0 (1 bit)

SCIE : SCIE
bits : 1 - 1 (1 bit)

SEIE : SEIE
bits : 2 - 2 (1 bit)

SUEIE : SUEIE
bits : 3 - 3 (1 bit)

CMDTCIE : CMDTCIE
bits : 4 - 4 (1 bit)

TCF : TCF
bits : 0 - 0 (1 bit)

SCF : SCF
bits : 1 - 1 (1 bit)

SEF : SEF
bits : 2 - 2 (1 bit)

SUEF : SUEF
bits : 3 - 3 (1 bit)

CMDTCF : CMDTCF
bits : 4 - 4 (1 bit)

CTCF : CTCF
bits : 0 - 0 (1 bit)

CSCF : CSCF
bits : 1 - 1 (1 bit)

CSEF : CSEF
bits : 2 - 2 (1 bit)

CSUEF : CSUEF
bits : 3 - 3 (1 bit)

CCMDTCF : CCMDTCF
bits : 4 - 4 (1 bit)

SEM : SEM
bits : 0 - 15 (16 bit)

DUEIE : DUEIE
bits : 0 - 0 (1 bit)

DERIE : DERIE
bits : 1 - 1 (1 bit)

DEFIE : DEFIE
bits : 2 - 2 (1 bit)

DSRIE : DSRIE
bits : 3 - 3 (1 bit)

EPBRIE : EPBRIE
bits : 4 - 4 (1 bit)

DUEF : DUEF
bits : 0 - 0 (1 bit)

DERF : DERF
bits : 1 - 1 (1 bit)

DEFF : DEFF
bits : 2 - 2 (1 bit)

DSRF : DSRF
bits : 3 - 3 (1 bit)

EPBRF : EPBRF
bits : 4 - 4 (1 bit)

CDUEF : CDUEF
bits : 0 - 0 (1 bit)

CDERF : CDERF
bits : 1 - 1 (1 bit)

CDEFF : CDEFF
bits : 2 - 2 (1 bit)

CDSRF : CDSRF
bits : 3 - 3 (1 bit)

CEPBRF : CEPBRF
bits : 4 - 4 (1 bit)

BCHPB : BCHPB
bits : 0 - 31 (32 bit)

BCHPB : BCHPB
bits : 0 - 31 (32 bit)

BCHPB : BCHPB
bits : 0 - 31 (32 bit)

BCHPB : BCHPB
bits : 0 - 31 (32 bit)

DUE : DUE
bits : 0 - 0 (1 bit)

DEF : DEF
bits : 1 - 1 (1 bit)

DEN : DEN
bits : 4 - 7 (4 bit)

EBP0_13 : EBP0_13
bits : 0 - 12 (13 bit)

EBP16_28 : EBP16_28
bits : 13 - 13 (1 bit)

EBP0_13 : EBP0_13
bits : 0 - 12 (13 bit)

EBP16_28 : EBP16_28
bits : 13 - 13 (1 bit)

EBP0_13 : EBP0_13
bits : 0 - 12 (13 bit)

EBP16_28 : EBP16_28
bits : 13 - 13 (1 bit)

EBP0_13 : EBP0_13
bits : 0 - 12 (13 bit)

EBP16_28 : EBP16_28
bits : 13 - 13 (1 bit)

RD_LN2DPTH : RD_LN2DPTH
bits : 0 - 3 (4 bit)

NOR_BASE : NOR_BASE
bits : 4 - 4 (1 bit)

SDRAM_RBASE : SDRAM_RBASE
bits : 8 - 8 (1 bit)

NAND_BASE : NAND_BASE
bits : 12 - 15 (4 bit)

SDRAM1_BASE : SDRAM1_BASE
bits : 16 - 19 (4 bit)

SDRAM2_BASE : SDRAM2_BASE
bits : 20 - 23 (4 bit)

NAND_SEL : NAND_SEL
bits : 0 - 0 (1 bit)

NAND_ECC : NAND_ECC
bits : 4 - 4 (1 bit)

SDRAM_SEL : SDRAM_SEL
bits : 8 - 8 (1 bit)

ID_SIZE : ID_SIZE
bits : 12 - 15 (4 bit)

WA_LN2DPTH : WA_LN2DPTH
bits : 16 - 19 (4 bit)

WD_LN2DPTH : WD_LN2DPTH
bits : 20 - 23 (4 bit)

WR_LN2DPTH : WR_LN2DPTH
bits : 24 - 27 (4 bit)

RA_LN2DPTH : RA_LN2DPTH
bits : 28 - 31 (4 bit)

MINREV : MINREV
bits : 0 - 3 (4 bit)

MAJREV : MAJREV
bits : 4 - 7 (4 bit)

ID : ID
bits : 0 - 31 (32 bit)

SID : SID
bits : 0 - 31 (32 bit)

ADDSET : Address setup phase duration These bits are written by software to define the duration of the address setup phase (refer to Figure81 to Figure93), used in SRAMs, ROMs and asynchronous NOR Flash: For each access mode address setup phase duration, please refer to the respective figure (refer to Figure81 to Figure93). Note: In synchronous accesses, this value is dont care. In Muxed mode or Mode D, the minimum value for ADDSET is 1.
bits : 0 - 3 (4 bit)

ADDHLD : Address-hold phase duration These bits are written by software to define the duration of the address hold phase (refer to Figure81 to Figure93), used in mode D or multiplexed accesses: For each access mode address-hold phase duration, please refer to the respective figure (Figure81 to Figure93). Note: In synchronous accesses, this value is not used, the address hold phase is always 1 memory clock period duration.
bits : 4 - 7 (4 bit)

DATAST : Data-phase duration These bits are written by software to define the duration of the data phase (refer to Figure81 to Figure93), used in asynchronous accesses: For each memory type and access mode data-phase duration, please refer to the respective figure (Figure81 to Figure93). Example: Mode1, write access, DATAST=1: Data-phase duration= DATAST+1 = 2 KCK_FMC clock cycles. Note: In synchronous accesses, this value is dont care.
bits : 8 - 15 (8 bit)

BUSTURN : Bus turnaround phase duration These bits are written by software to add a delay at the end of a write-to-read or read-to write transaction. The programmed bus turnaround delay is inserted between an asynchronous read (in muxed or mode D) or write transaction and any other asynchronous /synchronous read/write from/to a static bank. If a read operation is performed, the bank can be the same or a different one, whereas it must be different in case of write operation to the bank, except in muxed mode or mode D. In some cases, whatever the programmed BUSTRUN values, the bus turnaround delay is fixed as follows: The bus turnaround delay is not inserted between two consecutive asynchronous write transfers to the same static memory bank except in muxed mode and mode D. There is a bus turnaround delay of 1 FMC clock cycle between: Two consecutive asynchronous read transfers to the same static memory bank except for modes muxed and D. An asynchronous read to an asynchronous or synchronous write to any static bank or dynamic bank except in modes muxed and D mode. There is a bus turnaround delay of 2 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to the same bank. A synchronous write (burst or single) access and an asynchronous write or read transfer to or from static memory bank (the bank can be the same or a different one in case of a read operation. Two consecutive synchronous read operations (in Burst or Single mode) followed by any synchronous/asynchronous read or write from/to another static memory bank. There is a bus turnaround delay of 3 FMC clock cycle between: Two consecutive synchronous write operations (in Burst or Single mode) to different static banks. A synchronous write access (in Burst or Single mode) and a synchronous read from the same or a different bank. The bus turnaround delay allows to match the minimum time between consecutive transactions (tEHEL from NEx high to NEx low) and the maximum time required by the memory to free the data bus after a read access (tEHQZ): (BUSTRUN + 1) KCK_FMC period ≥ tEHELmin and (BUSTRUN + 2)KCK_FMC period ≥ tEHQZmax if EXTMOD = 0 (BUSTRUN + 2)KCK_FMC period ≥ max (tEHELmin, tEHQZmax) if EXTMOD = 126. ...
bits : 16 - 19 (4 bit)

CLKDIV : Clock divide ratio (for FMC_CLK signal) These bits define the period of FMC_CLK clock output signal, expressed in number of KCK_FMC cycles: In asynchronous NOR Flash, SRAM or PSRAM accesses, this value is dont care. Note: Refer to Section20.6.5: Synchronous transactions for FMC_CLK divider ratio formula)
bits : 20 - 23 (4 bit)

DATLAT : Data latency for synchronous memory For synchronous access with read write burst mode enabled these bits define the number of memory clock cycles
bits : 24 - 27 (4 bit)

ACCMOD : Access mode These bits specify the asynchronous access modes as shown in the timing diagrams. They are taken into account only when the EXTMOD bit in the FMC_BCRx register is 1.
bits : 28 - 29 (2 bit)

DATAHLD : DATAHLD
bits : 30 - 31 (2 bit)

MBKEN : Memory bank enable bit This bit enables the memory bank. After reset Bank1 is enabled, all others are disabled. Accessing a disabled bank causes an ERROR on AXI bus.
bits : 0 - 0 (1 bit)

MUXEN : Address/data multiplexing enable bit When this bit is set, the address and data values are multiplexed on the data bus, valid only with NOR and PSRAM memories:
bits : 1 - 1 (1 bit)

MTYP : Memory type These bits define the type of external memory attached to the corresponding memory bank:
bits : 2 - 3 (2 bit)

MWID : Memory data bus width Defines the external memory device width, valid for all type of memories.
bits : 4 - 5 (2 bit)

FACCEN : Flash access enable This bit enables NOR Flash memory access operations.
bits : 6 - 6 (1 bit)

BURSTEN : Burst enable bit This bit enables/disables synchronous accesses during read operations. It is valid only for synchronous memories operating in Burst mode:
bits : 8 - 8 (1 bit)

WAITPOL : Wait signal polarity bit This bit defines the polarity of the wait signal from memory used for either in synchronous or asynchronous mode:
bits : 9 - 9 (1 bit)

WAITCFG : Wait timing configuration The NWAIT signal indicates whether the data from the memory are valid or if a wait state must be inserted when accessing the memory in synchronous mode. This configuration bit determines if NWAIT is asserted by the memory one clock cycle before the wait state or during the wait state:
bits : 11 - 11 (1 bit)

WREN : Write enable bit This bit indicates whether write operations are enabled/disabled in the bank by the FMC:
bits : 12 - 12 (1 bit)

WAITEN : Wait enable bit This bit enables/disables wait-state insertion via the NWAIT signal when accessing the memory in synchronous mode.
bits : 13 - 13 (1 bit)

EXTMOD : Extended mode enable. This bit enables the FMC to program the write timings for asynchronous accesses inside the FMC_BWTR register, thus resulting in different timings for read and write operations. Note: When the extended mode is disabled, the FMC can operate in Mode1 or Mode2 as follows: ** Mode 1 is the default mode when the SRAM/PSRAM memory type is selected (MTYP =0x0 or 0x01) ** Mode 2 is the default mode when the NOR memory type is selected (MTYP = 0x10).
bits : 14 - 14 (1 bit)

ASYNCWAIT : Wait signal during asynchronous transfers This bit enables/disables the FMC to use the wait signal even during an asynchronous protocol.
bits : 15 - 15 (1 bit)

CPSIZE : CRAM Page Size These are used for Cellular RAM 1.5 which does not allow burst access to cross the address boundaries between pages. When these bits are configured, the FMC controller splits automatically the burst access when the memory page size is reached (refer to memory datasheet for page size). Other configuration: reserved.
bits : 16 - 18 (3 bit)

CBURSTRW : Write burst enable For PSRAM (CRAM) operating in Burst mode, the bit enables synchronous accesses during write operations. The enable bit for synchronous read accesses is the BURSTEN bit in the FMC_BCRx register.
bits : 19 - 19 (1 bit)

CCLKEN : Continuous Clock Enable This bit enables the FMC_CLK clock output to external memory devices. Note: The CCLKEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register. Bank 1 must be configured in synchronous mode to generate the FMC_CLK continuous clock. If CCLKEN bit is set, the FMC_CLK clock ratio is specified by CLKDIV value in the FMC_BTR1 register. CLKDIV in FMC_BWTR1 is dont care. If the synchronous mode is used and CCLKEN bit is set, the synchronous memories connected to other banks than Bank 1 are clocked by the same clock (the CLKDIV value in the FMC_BTR2..4 and FMC_BWTR2..4 registers for other banks has no effect.)
bits : 20 - 20 (1 bit)

NBLSET : NBLSET
bits : 22 - 23 (2 bit)

FMCEN : FMC controller Enable This bit enables/disables the FMC controller. Note: The FMCEN bit of the FMC_BCR2..4 registers is dont care. It is only enabled through the FMC_BCR1 register.
bits : 31 - 31 (1 bit)

PWAITEN : Wait feature enable bit. This bit enables the Wait feature for the NAND Flash memory bank:
bits : 1 - 1 (1 bit)

PBKEN : NAND Flash memory bank enable bit. This bit enables the memory bank. Accessing a disabled memory bank causes an ERROR on AXI bus
bits : 2 - 2 (1 bit)

PWID : Data bus width. These bits define the external memory device width.
bits : 4 - 5 (2 bit)

ECCEN : ECC computation logic enable bit
bits : 6 - 6 (1 bit)

ECCALG : ECCALG
bits : 8 - 8 (1 bit)

TCLR : CLE to RE delay. These bits set time from CLE low to RE low in number of KCK_FMC clock cycles. The time is give by the following formula: t_clr = (TCLR + SET + 2) TKCK_FMC where TKCK_FMC is the KCK_FMC clock period Note: Set is MEMSET or ATTSET according to the addressed space.
bits : 9 - 12 (4 bit)

TAR : ALE to RE delay. These bits set time from ALE low to RE low in number of KCK_FMC clock cycles. Time is: t_ar = (TAR + SET + 2) TKCK_FMC where TKCK_FMC is the FMC clock period Note: Set is MEMSET or ATTSET according to the addressed space.
bits : 13 - 16 (4 bit)

ECCSS : ECCSS
bits : 17 - 19 (3 bit)

BCHECC : BCHECC
bits : 24 - 24 (1 bit)

WEN : WEN
bits : 25 - 25 (1 bit)

ISOST : ISOST
bits : 0 - 1 (2 bit)
access : read-only

PEF : PEF
bits : 4 - 4 (1 bit)
access : read-only

NWRF : NWRF
bits : 6 - 6 (1 bit)
access : read-only

MEMSET : Common memory x setup time These bits define the number of KCK_FMC (+1) clock cycles to set up the address before the command assertion (NWE, NOE), for NAND Flash read or write access to common memory space:
bits : 0 - 7 (8 bit)

MEMWAIT : Common memory wait time These bits define the minimum number of KCK_FMC (+1) clock cycles to assert the command (NWE, NOE), for NAND Flash read or write access to common memory space. The duration of command assertion is extended if the wait signal (NWAIT) is active (low) at the end of the programmed value of KCK_FMC:
bits : 8 - 15 (8 bit)

MEMHOLD : Common memory hold time These bits define the number of KCK_FMC clock cycles for write accesses and KCK_FMC+1 clock cycles for read accesses during which the address is held (and data for write accesses) after the command is de-asserted (NWE, NOE), for NAND Flash read or write access to common memory space:
bits : 16 - 23 (8 bit)

MEMHIZ : Common memory x data bus Hi-Z time These bits define the number of KCK_FMC clock cycles during which the data bus is kept Hi-Z after the start of a NAND Flash write access to common memory space. This is only valid for write transactions:
bits : 24 - 31 (8 bit)