SBOSA45D February 2022 – January 2025 TMP1826
PRODUCTION DATA
Table 8-9 shows the correct procedure the host must execute to update the EEPROM. When communicating with a single device, the host can use the SKIPADDR command. However when communicating with multiple devices, the host must use the MATCHADDR command or the FLEXADDR command to address the correct device. The host writes to the EEPROM scratchpad first, reads the scratchpad back to verify the content before the host copies the same information to the user EEPROM. The copy command is issued with the qualifier byte A5h and the bus is held idle for the duration of erase and program of the EEPROM. The host shall repeat the sequence for every 8 byte page. After the locations are programmed, the host can issue an READ EEPROM function with the start address to read all the bytes. The device shall read back the bytes in page size and put a CRC byte after every page to verify that the host shall be able to identify bit corruption using the CRC over a smaller data packet.
As long as the host continues the read operation, the device shall read back 8 bytes of data followed by a CRC byte. When the device reaches the end of the EEPROM block, the device shall return all 1's to the host.
HOST TO DEVICE | DEVICE TO HOST | COMMENTS |
---|---|---|
Reset | Host sends reset to initialize communication | |
Answer to Reset | Device responds to initialization | |
SKIPADDR (CCh) | Host sends address command to select all devices | |
WRITE SCRATCHPAD-2 (0Fh) | Host sends function command to write to scratchpad-2 | |
2-byte EEPROM Address | Host sends 2-byte EEPROM address where data has to be written with MSB first and LSB last | |
8-bytes data | Host sends 8-byte data for the EEPROM address | |
CRC | Device sends CRC for the address and data | |
Reset | Host sends reset to initialize communication | |
Answer to Reset | Device responds to initialization | |
SKIPADDR (CCh) | Host sends address command to select all devices | |
READ SCRATCHPAD-2 (AAh) | Host sends function command to read from scratchpad-2 | |
2-byte EEPROM Address | Host sends 2-byte EEPROM address for which data has been written with MSB first and LSB last | |
8-bytes data | Device sends 8 bytes from scratchpad-2 | |
CRC | Device sends CRC for the 8 bytes | |
Reset | Host sends reset to initialize communication | |
Answer to Reset | Device responds to initialization | |
SKIPADDR (CCh) | Host sends address command to select all devices | |
COPY SCRATCHPAD-2 (55h) | Host sends function command to copy scratchpad-2 to EEPROM | |
A5h | Host sends qualifier byte for EEPROM program | |
Bus idle for tPROG | Bus is held in idle state (high) during EEPROM programming | |
Reset | Host sends reset to initialize communication | |
Answer to Reset | Device responds to initialization | |
SKIPADDR (CCh) | Host sends address command to select all devices | |
READ EEPROM (F0h) | Host sends function command to read EEPROM | |
2-byte EEPROM Address | Host sends 2-byte address to the EEPROM to read data | |
Bus idle for tREADIDLE | Bus is held in idle state (high) during read to prefetch the data | |
8-bytes data | Device sends 8 bytes from EEPROM address | |
CRC | Device sends CRC for the 8 bytes | |
Bus idle for tREADIDLE | Bus is held in idle state (high) during read to prefetch the data |