330 disable function bug

68030 + SDRAM + IDE

Moderators: terriblefire, Terriblefire Moderator

alenppc
Moderator Team
Moderator Team
Posts: 906
Joined: Thu Nov 08, 2018 12:59 pm

330 disable function bug

Post by alenppc »

Some people have observed that the disable function does not work correctly. I have already spoken with Stephen about this, but I thought I'd post for the rest who may not know about this yet.

Basically, the disable function (when the jumper is removed) will fail intermittently. On certain occasions, the console will boot in 68020 mode but crash shortly after as the 68030 unexpectedly comes to life (it will get quite hot quickly).
In other occasions, both CPUs will become active at powerup, even if the jumper is removed.

I have been able to reproduce this consistently with multiple cards. I am not sure what causes it, but Stephen has devised a tentative fix that involves adding resistors. I haven't had the chance to test it yet though.
terriblefire
Moderator Team
Moderator Team
Posts: 5368
Joined: Mon Aug 28, 2017 10:56 pm
Location: Glasgow, UK

Re: 330 disable function bug

Post by terriblefire »

I think this is caused by a floating pin. I’ve put a big pull down on the latest TF330 order.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
alenppc
Moderator Team
Moderator Team
Posts: 906
Joined: Thu Nov 08, 2018 12:59 pm

Re: 330 disable function bug

Post by alenppc »

Tested the hardware fix today, but the 68030 still comes to life after a few minutes.
terriblefire
Moderator Team
Moderator Team
Posts: 5368
Joined: Mon Aug 28, 2017 10:56 pm
Location: Glasgow, UK

Re: 330 disable function bug

Post by terriblefire »

alenppc wrote: Sat May 18, 2019 9:35 pm Tested the hardware fix today, but the 68030 still comes to life after a few minutes.
I will try and come up with a firmware update to latch the DISABLE state on reset.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
User avatar
8 Bit Dreams
Moderator Team
Moderator Team
Posts: 785
Joined: Fri Nov 09, 2018 7:12 am
Location: Germany

Re: 330 disable function bug

Post by 8 Bit Dreams »

Ok,
Can confirm, disable function isn't working properly, 030 gets very hot, black or green screen
Retro computer hardware & repair in Germany
terriblefire
Moderator Team
Moderator Team
Posts: 5368
Joined: Mon Aug 28, 2017 10:56 pm
Location: Glasgow, UK

Re: 330 disable function bug

Post by terriblefire »

I havent tested this one but if anyone wants to try out my firmware fix for the reset bug here it is..
tf330_2019_05_24_alpha.zip
(23.72 KiB) Downloaded 271 times
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
alenppc
Moderator Team
Moderator Team
Posts: 906
Joined: Thu Nov 08, 2018 12:59 pm

Re: 330 disable function bug

Post by alenppc »

I am getting no change in behaviour... both with the hw fixed and the regular cards... Can anyone else try this?
User avatar
supaduper
Posts: 561
Joined: Thu Nov 08, 2018 12:05 pm

Re: 330 disable function bug

Post by supaduper »

Already have and reported the same as you to Steve yesterday
theq
Posts: 114
Joined: Tue Dec 18, 2018 7:16 pm
Location: North of the Wall

Re: 330 disable function bug

Post by theq »

With disable function you mean removing the jumper that makes this thing tick?
If so, how would I see if the 330 suddenly starts ticking again, by a hang/restart?

Reason why I'm asking is that I have removed the jumper and played one (1) game (Cannon Fodder) continuously for 1,5 hours without any problems. Didn't reset or try any other games with the power on, though.

And, mind me for asking, why have a disable "switch" anyhow? The other expansions like SX-32 don't have it. You would just remove the card to revert to vanilla state.
terriblefire
Moderator Team
Moderator Team
Posts: 5368
Joined: Mon Aug 28, 2017 10:56 pm
Location: Glasgow, UK

Re: 330 disable function bug

Post by terriblefire »

Its to save wear on the edge connectors.

The disable function doesnt just stop the thing "ticking" it switches from holding the 020 inactive to holding the 030 inactive. My guess is some noise is causing an issue.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
Post Reply

Return to “TF330”