SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
The Z1 GPREG2 register in OTP can selectively enable and disable write protection for selected Flash sectors in Flash banks 0 and 2. When the selected bits are programmed to a value of 0, the corresponding sectors can no longer be erased or programmed. This capability allows the user to create immutable Flash regions and along with the DCSM security module can be used to realize new secure code functions, including authentication algorithms.
Table 4-15 explains how the bit field values from the user configurable DCSM OTP location, Z1-OTP-BOOT-GPREG2 or Z2-OTP-BOOT-GPREG2, are decoded by boot ROM.
Bit | Name | Description | Boot ROM Action |
---|---|---|---|
31:24 | Key | Write 0x5A to indicate to the boot ROM code that the bits in this register are valid. | If user sets to 0x5A, boot ROM uses the values in this register. If set to any other value, boot ROM ignores values in this register. |
23(2) | WPROT_BANK2_SEC_28_31 | Write Protect Flash Bank 2 Sectors 28-31 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
22(2) | WPROT_BANK2_SEC_24_27 | Write Protect Flash Bank 2 Sectors 24-27 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
21(2) | WPROT_BANK2_SEC_20_23 | Write Protect Flash Bank 2 Sectors 20-23 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
20(2) | WPROT_BANK2_SEC_16_19 | Write Protect Flash Bank 2 Sectors 16-19 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
19(2) | WPROT_BANK2_SEC_12_15 | Write Protect Flash Bank 2 Sectors 12-15 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
18(2) | WPROT_BANK2_SEC_8_11 | Write Protect Flash Bank 2 Sectors 8-11 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
17(2) | WPROT_BANK2_SEC_0_7 | Write Protect Flash Bank 2 Sectors 0-7 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
16(2) | Reserved | Reserved | No Action |
15(2) | WPROT_BANK0_SEC_28_31 | Write Protect Flash Bank 0 Sectors 28-31 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
14(2) | WPROT_BANK0_SEC_24_27 | Write Protect Flash Bank 0 Sectors 24-27 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
13(2) | WPROT_BANK0_SEC_20_23 | Write Protect Flash Bank 0 Sectors 20-23 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
12(2) | WPROT_BANK0_SEC_16_19 | Write Protect Flash Bank 0 Sectors 16-19 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
11(2) | WPROT_BANK0_SEC_12_15 | Write Protect Flash Bank 0 Sectors 12-15 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
10(2) | WPROT_BANK0_SEC_8_11 | Write Protect Flash Bank 0 Sectors 8-11 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
9(2) | WPROT_BANK0_SEC_0_7 | Write Protect Flash Bank 0 Sectors 0-7 | 0: Flash sectors cannot be erased or programmed 1: Flash sectors can be erased or programmed |
8:7 | MPOST(1) | 0x0 = Run MPOST with PLL disabled (10MHz internal oscillator) |
When configured to a valid value, MPOST POR memory self-test runs on all device memories |
0x1 = Run MPOST with PLL enabled for 150MHz | |||
0x2 = Run MPOST with PLL enabled for 75MHz | |||
0x3 = Disable MPOST | |||
6:4 | ERROR_ STS_PIN configuration |
0x0 – GPIO24, MUX Option 13 | This indicates which GPIO pin is supposed to be used as ERROR_PIN and boot ROM configures the mux the pin. The ERROR_STS pin mux configuration is locked by the boot ROM, but is not committed. |
0x1 – GPIO28, MUX Option 13 | |||
0x2 – GPIO29, MUX Option 13 | |||
0x3 – ERROR_STS function disabled | |||
0x4 – GPIO55, MUX Option 9 | |||
0x5 – GPIO64, MUX Option 13 | |||
0x6 – GPIO73, MUX Option 13 | |||
0x7 – ERROR_STS function disabled (default) | |||
3:0 | CJTAGNODEID | CJTAGNODEID[3:0] | Boot ROM takes this values and programs the lower 4 bits of the CJTAGNODEID register. |