Help required to make 24CXX programmer

[Athar Rasul]

Hi

I want to make a programmer for 24Cxx family of EEPROMs. I am using JDM's following circuit:

**broken link removed**

I have 2 questions:

1. Can I use 9-pin serial instead of 25-pin? Will that disturb voltage levels as JDM has stated that it only works with RS-232 levels at < ±7V.

2. Can I only connect the required pins for EEPROM (boxed in green) and leave rest of the pins without having to worry about floating etc?

Thanks

Added after 10 minutes:

If not this circuit, can the uJDM work for EEPROM?
**broken link removed**
I believe it is for PIC only.

 

[Athar Rasul]

Kindly someone take notice.. I've been stuck on this and need help....

 

[spiralbrain]

yes a DB9 will do fine from an RS232 port. It does require a + and - voltage to work as a PIC needs more than 5v to erase. And yes you can connect the pins in green and it should work. the others are only used for a PIC microcontroller.

 

[daltanics]

yes a DB9 will do fine from an RS232 port. It does require a + and - voltage to work as a PIC needs more than 5v to erase. And yes you can connect the pins in green and it should work. the others are only used for a PIC microcontroller.

yes that can be possible try this layout thru protues 7.1