Serial EEPROM Connected to the PowerSpan

FLASH EEPROM Programming Algorithms

The boot memory is a 4Mx8 AMD 29LV033 FLASH device. To reprogram the AMD FLASH device, special programming algorithms are defined by AMD, which combine reads and writes with special address patterns. The algorithm descriptions can be found at the AMD web site. You can also look or start from the source provided in the BDK (file app\c\amdflash.c).

Serial EEPROM Connected to the PowerSpan

An I²C serial EEPROM is connected to the PowerSpan. It is used to store certain PowerSpan register initialization values and the PCI Vital Product Data (VPD). Other Interphase-specific data is stored there, and there is still some room for other custom data. See “Serial EEPROM Connected to the PowerSpan” on page 27.

Table 2-1 on page 60 provides the PowerSpan Register initialization values stored in the Serial EEPROM.

The I²C Serial EEPROM can be easily accessed from the PCI side or from the local processor side, by using dedicated PowerSpan Register I2C_CSR.

Example 4-6is an example of C code read and write routines.

Example 4-6. I²C Serial EEPROM Read and Write Routines (From PCI Side)

XQVLJQHG￿FKDU￿(HSURP%\WH5HDG￿￿XQVLJQHG￿FKDU￿D￿

^

XQVLJQHG￿ORQJ￿Y￿

Y￿ ￿￿￿XQVLJQHG￿ORQJ￿￿D￿￿￿￿￿￿_￿￿[$￿￿￿￿

ZKLOH￿￿5HJ5HDG￿￿￿￿7B,￿&B&65￿￿￿￿￿[￿￿￿￿￿￿￿￿￿:DLW￿$&7 ￿ 5HJ:ULWH￿￿￿￿7B,￿&B&65￿￿Y￿￿

ZKLOH￿￿￿Y 5HJ5HDG￿￿￿￿7B,￿&B&65￿￿￿￿￿[￿￿￿￿￿￿￿￿￿￿:DLW￿$&7 ￿ LI￿￿Y￿￿[￿￿￿￿SULQWI￿￿HUURU￿￿￿

Y!! ￿￿￿

UHWXUQ￿￿XQVLJQHG￿FKDU￿￿Y￿

`

YRLG￿(HSURP%\WH:ULWH￿￿XQVLJQHG￿FKDU￿D￿￿XQVLJQHG￿FKDU￿G￿

^

XQVLJQHG￿ORQJ￿Y￿V￿

Y￿ ￿￿￿XQVLJQHG￿ORQJ￿￿D￿￿￿￿￿￿_￿￿XQVLJQHG￿ORQJ￿￿G￿￿￿￿￿￿_￿￿[$￿￿￿￿

ZKLOH￿￿V 5HJ5HDG￿￿￿￿7B,￿&B&65￿￿￿￿￿￿[￿￿￿￿￿￿￿￿￿:DLW￿$&7 ￿ LI￿￿V￿￿[￿￿￿￿SULQWI￿￿HUURU￿￿￿

5HJ:ULWH￿￿￿￿7B,￿&B&65￿￿Y￿￿

`

92

Interphase Corporation