Replicape / libs / i2c-tools-3.1.0 / eepromer / README.eeprom

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You can use this program to read/write to i2c-eeproms
like the popular 24C16, 24C08, 24C04,.. In contrast to eeprommer
which supports 24C256-type eeproms 24C16ss use 1-byte addresses!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Warning !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!                                                                           !
!!! This program should only be used on external busses such as i2c-pport.    !
!!!                                                                           !
!!! Your computer may contain i2c-eeproms for saving data vital to its       !
!!! operation. If you are not careful you might overwrite this data with      !
!!! this program and your computer may no longer boot!                        !
!!!                                                                           !
!!! An example are the EEPROMS on your SDRAM DIMMs, your computer may no      !
!!! longer detect the RAM module rendering it essentially USELESS!            !
!!!                                                                           !
!!! IBM Thinkpads are said to store their configuration data in a eeprom,     !
!!! if you manage to overwrite this eeprom you will have to send your         !
!!! computer to the manufacturer for a costly repair!                         !
!!!                                                                           !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Warning !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

It has several options:

	-d devicenode

		set this to the device-node of the i2c-bus
		you want to use like /dev/i2c-0.
		Use /dev/i2c-1 for the second bus, i2c-2 for the third...

		The default /dev/i2c-0 should work most of the time.

	-a address

		set this to the device-address of your
		eeprom. For a 24C16 the address is hardcoded to
		0x50, which is -you guessed it- the default.

		For a 24C08 and smaller types you can choose which
		addresses they occupy by forcing the address-pins
		of the chip to High or Low so here the address may differ.

	-p number_of_pages

		set this to the number of pages you want to read
		from or write to the eeprom. The 24C16 maps it's
		pages to consecutive addresses on the i2c-bus so
		we will try to read 256 bytes from every i2c
		address between 'address' (inclusive) and
		'address + number_of_pages' (exclusive)...

		A 24C16 has 8 pages so that's the default for this

	-f filename

		read data from this file (when writing to eeprom) or
		write data to this file (when reading from eeprom).

		When reading a file that's smaller than the
		eeprom's storage size we will pad the eeprom
		with zeroes.

		If no file is given we will just read the
		eeprom (while in read-mode) and test it's presence
		this way. In write-mode we will just write zeroes
		to the eeprom.

	-w	When '-w' is present we will *write* to the eeprom.
		If you do not specify '-w' we will read the contents
		of the eeprom.

	-y	This flag will suppress the warning when you write to the
		eeprom. You will not be required to enter 'yes' so be careful
		when using this switch!

I wrote that program to clear a 24C16 eeprom that sit's in my crappy
satellite receiver because sometimes its Z80 processor likes to
write garbage to it and then crash....

No further testing besides writing a long series of "The quick brown
fox jumps over the lazy dog!" and reading it back has been done so
of course this comes without any warranty.

	Chris <>