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Re: CPLD replacement for ZX8301
Posted: Sat Sep 24, 2022 5:10 pm
by lliont
I published the pcb and EPM160S files at the hackaday.io site,
https://hackaday.io/projects/hacker/357657
Re: CPLD replacement for ZX8301
Posted: Sat Sep 24, 2022 5:53 pm
by Derek_Stewart
Thanks I have downloaded all the files, I will see about making some PCBs...
Re: CPLD replacement for ZX8301
Posted: Sun Sep 25, 2022 10:22 am
by Peter
Although I have no personal need for a ZX8301 replacement, my greatest respect and appreciation for this excellent work!
Also for your QUBIDE clone, a very thoughtful and nice design as well.
Re: CPLD replacement for ZX8301
Posted: Wed Oct 19, 2022 8:13 pm
by lliont
Thank you Peter
Here a new pcb with the EPM7160STC100-10 that is smd and fits also in QL's with socketed rams.
It was difficult to solder it now that I'm older and can't see very well but finally I did it.
It gets hot, hotter than the PLCC84 cpld, I'll put a small flat heat-sink on it even I don't think it is necessary, now there is enough space.
Re: CPLD replacement for ZX8301
Posted: Thu Oct 20, 2022 12:22 pm
by lliont
Re: CPLD replacement for ZX8301
Posted: Thu Oct 20, 2022 2:49 pm
by Pr0f
kudos to the soldering skills for that beast - was that done using a lot of flux and dragging a blob technique, as no one has an iron that small

Re: CPLD replacement for ZX8301
Posted: Thu Oct 20, 2022 4:46 pm
by mk79
Pr0f wrote:kudos to the soldering skills for that beast - was that done using a lot of flux and dragging a blob technique, as no one has an iron that small

I have a soldering iron this small but still prefer the drag technique

Nice job anyway, I just wonder if it's normal that it would get this hot.
Re: CPLD replacement for ZX8301
Posted: Thu Oct 20, 2022 9:30 pm
by lliont
Don't know but it is a 5 volt small device with almost all its macro-cells used, clocked at 10 and 15Mhz (clocks derived from a 30Mhz active oscillator) and continually drives a lot of QL lines, maybe it is normal. It runs for hours with no problem so far with that small heatsink. You can touch the heatsink only for a couple of seconds.
Powered from an external ps when I was programing it not connected to the QL the whole circuit drew about 200ma. Do you think there is something wrong with the ic;
from datasheet:
Supply power (P) versus frequency (fMAX in MHz) for MAX 7000 devices is calculated with the following equation: P = P INT + PIO = ICCINT × VCC + P IO
The P IO value, which depends on the device output load characteristics and switching frequency, can be calculated using the guidelines given in
Application Note 74 (Evaluating Power for Altera Devices).
Yes I used something like the dragging a blob technique with lot of flux
Re: CPLD replacement for ZX8301
Posted: Fri Oct 21, 2022 5:54 pm
by lliont
The turbo bit option was in auto by default, I change it to off and the temperature dropped without affecting the operation!
Now it gets just warm but not hot.
This is cool!
Re: CPLD replacement for ZX8301
Posted: Fri Oct 21, 2022 7:17 pm
by martyn_hill
Thank you Leon!
For the first time in QL history, we have a viable replacement for one of her core ULAs!
Truly, a magnificent accomplishment!