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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 <>