Pls, Help me identify this chip

[Azhar]

I couldn't find any datasheet for these chips  Is there a way or a method to test a chip in order to identify it or know what is job?

[fcb]

My guess is CLA means "configurable logic array" - probably a PAL/GAL.

Would help to know what it is from?

[SeanB]

Second one is probably a 65xx SIO chip, seeing as there are RS232 converter chips next to it, and you have baud rate setting links in the DIP arrays next to it.

First looks like it is a 6522 PIA chip. Look at the datasheet at

http://archive.6502.org/datasheets/mos_6522.pdf

and see if the pinout for supply and the data lines from the LS374 agree.

[Azhar]

Second one is probably a 65xx SIO chip, seeing as there are RS232 converter chips next to it, and you have baud rate setting links in the DIP arrays next to it.

First looks like it is a 6522 PIA chip. Look at the datasheet at

http://archive.6502.org/datasheets/mos_6522.pdf

and see if the pinout for supply and the data lines from the LS374 agree.

It is from this telecommunications device, not sure what is its purpose

[grumpydoc]

It is from this telecommunications device, not sure what is its purpose

It is an X.21 modem, says so on the front

[SeanB]

Diginet NTU, used for a dedicated digital line of 56k or 64K, using a diginet link from point to point. Didn't think many are still around, i took one apart a while ago when we were force upgraded as Telkom SA no longer has any frame relay equipment left in exchanges, and is changing them out to something newer.

What makes you think they are faulty, those things run essentially forever, only failing with lightning strikes. I still have the board somewhere in a box, though your one is a really aincent unit and probably not compatible with the newer( less than 15 years old) standards....

https://en.wikipedia.org/wiki/X.21

Basically it is a serial port that allows remote connections using a dedicated switched circuit through older ATM frame relay exchanges, so you can send digital serial data as if you had a direct wired connection between the 2 points instead of a packet switched network.

http://www.arcelect.com/X21_interface.htm

Basically a low speed means of sending data, though 20 years ago it was the gold standard for rock solid connectivity, on and up 24/7/365 and never dropping a packet unless the line was broken.