4.6.1 Status Register Bit Definitions

The following table list the Status register bit definitions.

Table 4-21. Status Register Bit Definitions
BitDescription
[31:29]Value of locked state of the AHB interface. These bits contain the same information as REQACCESS[2:0].
[28:20]Reserved
19Command when Busy. Indicates that a command was loaded while the controller was busy and is ignored. Once set all command operations are disabled.

Cleared by writing 1 to bit 2 in Table 4-25.

18Access denied. Indicates that read or write operations were denied due to protection systems, or that an illegal command was loaded. Once set all command operations are disabled.

Cleared by writing 1 to bit 1 in the Table 4-25.

17NVM deep power-down state, indicates NVM has entered DPD mode
  • 0: NVM operational
  • 1: NVM In deep power-down

There is delay of ~5 µs for the NVM to enter power-down and assert this bit from requesting power-down.

[16:15]RDBUFF3 (Read data buffer 3 = Read data buffer[255:192]) ECC status (2-bit error, 1 bit corrected)
  • 00: no error
  • 01: 1 bit corrected
  • 10: 2 bit detected
  • 11: 3 or more bits detected
[14:13]RDBUFF2 (Read data buffer 2 = Read data buffer[191:128]) ECC status (2-bit error, 1 bit corrected)
  • 00: no error
  • 01: 1 bit corrected
  • 10: 2 bit detected
  • 11: 3 or more bits detected
[12:11]RDBUFF1 (Read data buffer 1 = Read data buffer[127:64]) ECC status (2-bit error, 1 bit corrected)
  • 00: no error
  • 01: 1 bit corrected
  • 10: 2 bit detected
  • 11: 3 or more bits detected
[10:9]RDBUFF0 (Read data buffer 0 = Read data buffer[63:0]) ECC status (2-bit error, 1 bit corrected)
  • 00: no error
  • 01: 1 bit corrected
  • 10: 2 bit detected
  • 11: 3 or more bits detected
8Asserted for ECC2 (2 bit error). Valid after read and read assembly buffer.
7Asserted for ECC1 (1 bit correction). Valid after read and read assembly buffer.
6Asserted for refresh required. Valid after program operation.
5Asserted when write count is over threshold. Valid after program, verify, and read page status. The threshold value per eNVM page is 1000 or 10000 depending on the data retention period. For more information on programming cycles and retention time, see IGLOO® 2 FPGA and SmartFusion® 2 SoC FPGA Datasheet.
4Asserted for program failure due to page lock. Valid after program operation.
3Asserted for write verify failure. Valid after program operation.
2Asserted for erase verify failure. Valid after program operation.
1Asserted for verify failure. Valid only after verify operation.
0NVM Ready/busy
  • 0: Busy
  • 1: Ready
Table 4-22. NV_FREQRNG Calculations at Different M3_CLK Frequencies for All SmartFusion® 2 Devices
Standard MSS Frequencies
M3_CLK in MHz166142133100665033
NV_FREQRNG[3:0]0x70x60x 50x 40x 30x 20x 2
NV_FREQRNG[7:4]0x70x60x 50x 40x 30x 20x 2
NV_FREQRNG[7:0]0x770x660x550x440x330x220x22
Important: If M3_CLK is 166 MHz, clock period is 6.024 ns. NV_FREQRNG[3:0] = roundup(40 ns/6.024 ns) = 7.
Table 4-23. NV_PAGE_STATUS
BitDescription
1R/W page status select
0Reserved
Table 4-24.  INTEN[10:0]
BitDescription
10Command loaded when busy
9NVM command denied by protection
8NVM internal program operation is complete
7ECC2 (2-bit error)
6ECC1 (1-bit correction)
5Refresh required
4Write count is over threshold
3Program failure due to page lock.
2Reserved
1Reserved
0Verify failure
Table 4-25. CLRHINT[2:0]
BitDescription
2Clear the internal command when busy bit
1Clear the internal access denied flag
0Clear HINTERRUPT output