STE V1.5 32MHz BOOSTER - STATUS

[PhilC]

Sorry, that's the one I meant, pub got in the way of my memory banks.

Will have a look at those for use with my PAKs then I stead of the gals.

[exxos]

Sorry, that's the one I meant, pub got in the way of my memory banks.

Will have a look at those for use with my PAKs then I stead of the gals.

You have to be careful though as pin 4 is "power down" not all programmers have the ATF22V10 (thankfully mine did) but I didn't risk it and hardwired pin 4 to 0v just to make sure... really needs to be tested more, but I got "stung" with all this back in 2015 :roll:

[exxos]

LOOP 25 ~ hour and half with "fast mode".. The whole machine has been on all day already as well..

Really makes me wonder about the GAL's, as they couldn't even run with a 16MHz clock... bizzare...

Going to try 40MHz on this board now.. not expecting it will work, but no harm in trying....

[sandord]

LOOP 25 ~ hour and half with "fast mode".. The whole machine has been on all day already as well..

Really makes me wonder about the GAL's, as they couldn't even run with a 16MHz clock... bizzare...

Going to try 40MHz on this board now.. not expecting it will work, but no harm in trying....

Fingers crossed!

[exxos]

Loop 11 (does about 17 loops per hour) suprised its run for this long...

Will try and leave it on all day tomorrow...

Also looks like my pink TV is having issues as its constantly going out of sync and its not the cable or ST :( Will have to take it to bits monday and do some recapping see if I can bring it back to life...

[exxos]

Its died.. so 40MHz is still a no-go. Saying that, I will put back "slow mode" to rule out ROM speed issues..

[exxos]

Another quick update, 40MHz was left running all day Saturday, I'm not at home on weekends, so someone else was keeping a eye on it for me.. We don't actually know how long it was for, somewhere between 4-7 hours. This was without ROM running faster as I just wanted to test the raw CPU speed.. But basically I am not happy that is going to be reliable.

The ROM clearly is having issues at 40MHz. I am not really surprised about this as mentioned before. We are really down to a fine line of hardware tolerances on everything. So to keep a happy medium with everything, boosters will be running at 36MHz.

Users can of course remove the wait states on the ROM, and users could even try changing the oscillator for a 40MHz one. Clearly some people get lucky with this but it is to hit and miss to manufacture the booster with a 40MHz osc. Really though, other than 34% extra on integer division, there is not really any advantages to this speed.

In any case, it is pretty clear that these ATF chips are working a lot better than the original GAL's I was using.

So hopefully, finally, I can finish off a few of these boards and forget about this project for a while and work on something else :)

[troed]

In any case, it is pretty clear that these ATF chips are working a lot better than the original GAL's I was using.

That in itself is a great finding that hopefully will benefit other hw builders for years to come.

(My 22V10 -10 at home are Lattice, I checked)

/Troed

[exxos]

That in itself is a great finding that hopefully will benefit other hw builders for years to come.

(My 22V10 -10 at home are Lattice, I checked)

These are the 2 GAL's I have been using...

The top one works absolutely fine and is a genuine 7ns.

The bottom ones, basically overall don't work at all. If they do work, not a very long. These were 12ns/15ns type parts so obviously reprinted. Even so, 15ns parts are the ones I am using now (ATF) and work absolutely fine. They should be good up to 80MHz anyway. Even 25ns parts should be fine really. So I really don't know what the problem is with these chips. They just seem like really really bad tolerances or something. Can only really assume they are factory rejects or something. Or used chips which have been subject to a lot of abuse which has damaged then somehow.

IMG_3638.JPG

[sandord]

It's the chip mob!