GAL16V8D chip

If the part is bad, you may not be able to read the program. If it is readable, you need a simple programming device, such as the kind made by BPMicro. You may have to remove the chip and put in the programmer which will read and store the internal program. Then you can program a new chip and install it on the board.

I would google up the manufacturer of the part and ask them to recommend a programmer.

Thanks Bhankiii for your inputs.

Actually the chip is bad, we have confirmed this with a same chip from another functional board. I will check on this programming device.

thanks once again.

By the way, do i have to use a specific programmer or any other programmer will do.?

you will need a programmer for that chip family. However, these chips often have what is called a 'security fuse', as the company wants to prevent you from easily repairing the display for $2 when they can sell you a chip for $100.

http://www.latticesemi.com/lit/docs/datasheets/pal_gal/16v8.pdf?jsessionid=ba30a11084e2$3F$3F$3

Most chip suppliers can copy a chip that is not fuse protected for a small fee.

You can also buy programmers.

http://www.google.ca/search?hl=en&q=GAL16V8D++%2Bprogrammer&btnG=Search&meta=

Hi aurizon,

So if this being the case, how do i find out whether there is a security fuse in the chip? I thought i could copy the chip (from a known good board). Or alternatively, do i need to get back to the LCD display manufacturer to get the chip. Please advise.

thanks

If you send the good one to get copied and they say it is protected. Or you buy a programmer and it says on screen that it is protected.

yes, if it is fuse protected there are only two ways to get the program.

1 buy a new one

2 reverse engineer the dead one from the known good boards. This can cost a lot of time and money.

Any idea what made the first one break down? try and prevent this in the future.

You can also do an ebay search or google search for a third party company that may have spares, or buy a used machine for spares?

Often if the new parts is $100, and there is some demand, you can find a third party for 40% or so less. It also depends on your country.

thanks for ur inputs aurizon!

The 'LEAPER 48' IC programmer allows you to copy PAL's, but you have a couple of problems to overcome.

Firstly, finding a known, 'good' version of that particular PAL and secondly finding one which hasn't had the security fuse blown - this makes the program unreadable and you won't be able to copy it. You will need a programmer to check this and the fault might be something else!

Unless you have an ongoing requirement to test/repair these boards it would probably be cheaper to buy a new one and save yourself time and money.

Hi Tom,

Thanks for your input.

I have a known good chip from a functional board. If i used this chip as a master sample, are u saying that there is a possibility that the security fuse may be blown also?

Assuming that the security fuse is not blown, is there a possiblility of the programmer mess up this chip causing it to malfuction also. This is because I have only one more board left. If that also blow up, I have to run.

thanks..

If they are careless, the fuse will be intact. They may also leave it intact if they want to update it from time to time with low cost.

The programmer is unlikely to damage the PAL or rupture the fuse - this is blown when the chip is programmed initially.

I always copy every PAL and EPROM that comes across my bench and this gives me a good idea of how the manufacturer has overcome any design problems. You often find that the programs change throughout the life of the board and this sometimes makes them incompatible with earlier/later boards, having a range of program versions of the same PAL gives you a bit more chance of fixing the fault. It also means that the manufacturer often leaves the fuse intact until all the 'bugs' are sorted then freezes the program. You might be lucky - take it to a local repair shop and ask if they can check the program accessability - they might even make you a copy - be cheeky ask for a second copy to keep as a spare.

Thanks guys, u have been most helpful in my enquiries...