Serial EEPROM programmer
Programmer and reader of serial EEPROM memories 24CXX, 24LCXX, 93CXX and 93LCXX.
But there is a bug in software with the memory 24C32 - see feedback at the end
of this page.
I have not done any change in schematic, but I've remade PCB. Programmer is
connected to PC via parallel port a it doesn't need any external power supply.
Driver, programming software and schematic was downloaded from
http://www.sistudio.com, but in recent days
it is impossible so you can download these files on the end of this page.
Connector J1 and diode D2 are not actually placed and used on my programmer.
It serves only for external power supply in case of a problem with power supply
directly from parallel port. The connector Cannon 25 type is hooked 90 degrees
for PCBs. Sockets for ICs should be better ones.
There is no need of lots of components. The board is better leave without
a cover or box to obtain good access to sockets.
Printed circuit board :
The board is bigger, then could be. It is better to hold it and to obtain easy
access to sockets. The size is 38.1x53.34 mm.
Only one side is used and no additional wire connections are used.
Software of programmer is in file eepsoft.zip.
File eeprom.zip consists of following :
||Schematic - format OrCad 386
||Schematic library - format OrCad 386
||PCB - format OrCad 386
||Schematic - PostScript
||Components - PostScript 4x bigger
||PCB - PostScript 4x bigger
List of componets :
Row Quantity Ref Type
1 1 C1 22M/16V
2 3 D1,D2,D3 1N4148
3 1 J1 CON2 ARK120/2
4 1 P1 DB25M CAN 25 V 90
5 1 R1 10k R
6 1 U1 I2C_EEPROM DIL8
7 1 U2 3_Wire_EEPROM DIL8
It looks like there is a bug in software with 24C32 eeprom. I've got next mail:
> I have run
>into a bug concerning the I2C programming of an Atmel 24C32. The read
>cycle does not appear to be implemented properly in the software and
>actually causes the part to be written!
All the best and good luck from Petr Simandl
Last change : 13.3. 2000