If I remember correct, a MC27C4001.

Avant 32

Beobuddy wrote:

If I remember correct, a MC27C4001.

Don’t know why I wrote that as the 4001 is used for software for BS9000, 3000, etc. 
I meant to write 1001. All these eproms are OTP, one time programmable. So make sure which settopbox you need to control.  

Willem EPROM Programmer

http://www.mpu51.com/eprom/eprom.html

https://www.gotronik.pl/programatory/willem7.html

That looks ancient...

thank you very much, so you can do i was afraid she was protected in reading. I already have my perfect eprom in the living room TV, I would like to copy it in the bedroom, I will look for the programmer in the garage it is very old but I have it, in the meantime I buy a couple of empty eproms,

Before you spend the time and effort in trying to find the chip with the right specs (which might not be as easy as you may think), it's better to confirm whether your programmer supports the chip and you have the drivers and the PLCC32 adapter available! Just read out the chip multiple times and see whether the result is consistent and the data makes sense.
(I've had some bad experience with programmers that - in theory - were capable of handling certain EPROM's but in the end they just didn't do their job. 😭  Therefore I'm now leaning more towards a "try first, buy later" philosophy. )

You say you want to copy the EPROM STB-C from the old AVANT, but there were a large number of different programmed chips and upgrades.

Look at the WiKi HERE for the last ones I updated the list. Each chip has a "Software Version" and a "Table"

What Set Top boxes do you want to support on your old AVANT?

Because a large number of old AVANT's are scraped it would be easier to get an existing chip from an old unit being scraped.