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You can use this program to read/write to i2c-eeproms |
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like the popular 24C16, 24C08, 24C04,.. In contrast to eeprommer |
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which supports 24C256-type eeproms 24C16ss use 1-byte addresses! |
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Warning !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! |
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!!! ! |
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!!! This program should only be used on external busses such as i2c-pport. ! |
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!!! ! |
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!!! Your computer may contain i2c-eeproms for saving data vital to its ! |
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!!! operation. If you are not careful you might overwrite this data with ! |
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!!! this program and your computer may no longer boot! ! |
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!!! ! |
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!!! An example are the EEPROMS on your SDRAM DIMMs, your computer may no ! |
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!!! longer detect the RAM module rendering it essentially USELESS! ! |
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!!! ! |
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!!! IBM Thinkpads are said to store their configuration data in a eeprom, ! |
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!!! if you manage to overwrite this eeprom you will have to send your ! |
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!!! computer to the manufacturer for a costly repair! ! |
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!!! ! |
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Warning !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! |
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It has several options: |
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-d devicenode |
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set this to the device-node of the i2c-bus |
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you want to use like /dev/i2c-0. |
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Use /dev/i2c-1 for the second bus, i2c-2 for the third... |
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The default /dev/i2c-0 should work most of the time. |
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-a address |
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set this to the device-address of your |
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eeprom. For a 24C16 the address is hardcoded to |
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0x50, which is -you guessed it- the default. |
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For a 24C08 and smaller types you can choose which |
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addresses they occupy by forcing the address-pins |
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of the chip to High or Low so here the address may differ. |
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-p number_of_pages |
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set this to the number of pages you want to read |
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from or write to the eeprom. The 24C16 maps it's |
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pages to consecutive addresses on the i2c-bus so |
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we will try to read 256 bytes from every i2c |
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address between 'address' (inclusive) and |
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'address + number_of_pages' (exclusive)... |
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A 24C16 has 8 pages so that's the default for this |
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parameter. |
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-f filename |
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read data from this file (when writing to eeprom) or |
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write data to this file (when reading from eeprom). |
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When reading a file that's smaller than the |
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eeprom's storage size we will pad the eeprom |
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with zeroes. |
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If no file is given we will just read the |
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eeprom (while in read-mode) and test it's presence |
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this way. In write-mode we will just write zeroes |
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to the eeprom. |
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-w When '-w' is present we will *write* to the eeprom. |
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If you do not specify '-w' we will read the contents |
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of the eeprom. |
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-y This flag will suppress the warning when you write to the |
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eeprom. You will not be required to enter 'yes' so be careful |
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when using this switch! |
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I wrote that program to clear a 24C16 eeprom that sit's in my crappy |
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satellite receiver because sometimes its Z80 processor likes to |
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write garbage to it and then crash.... |
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No further testing besides writing a long series of "The quick brown |
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fox jumps over the lazy dog!" and reading it back has been done so |
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of course this comes without any warranty. |
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Chris <chris@hedonism.cx> |
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