Hi, I am reading the source code of rtl8139 network card in linux. there are some codes like this: static void eeprom_cmd(void __iomem *ee_addr, int cmd, int cmd_len) { int i;
/* Shift the command bits out. */ for (i = cmd_len - 1; i >= 0; i--) { int dataval = (cmd & (1
Did you get the data sheet of the controller chip?
-- Tauno Voipio tauno voipio (at) iki fi
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hi, I have the datasheet.but i can not any place intruduce how to opearte the EEPROM.
It appears to me that it is clocking data out serialy, one bit at a time. I would guess that EE_ENB represents the chip select (EECS) line. dataval is a single data bit. EE_SHIFT_CLK probably represents the clock line (EESK). dataval likely aligns with the data input pin (EEDI) for the rtl8139. The first writeb puts the clock in a known state and also presents the data bit. The second writeb presents the data and toggles the clock line. The final writeb toggles the clock back with 0 for the data. That would be my best guess. Look up SPI data transfer.
Good - now you know how to manupulate the serial EEPROM control bits.
Next, get the data sheet of the EEPROM chip.
-- Tauno Voipio tauno voipio (at) iki fi
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