Search found 163 matches

by Gyro Gearloose
Sat Jul 06, 2019 11:28 pm
Forum: Chit Chat
Topic: Commodore - from one storage to another!
Replies: 4
Views: 81

Re: Commodore - from one storage to another!

eslapion wrote:
Fri Jul 05, 2019 3:25 am
I am amazed a single human being can amass that much Commodore equipment!

Image
by Gyro Gearloose
Wed Jun 19, 2019 3:06 am
Forum: Help!
Topic: 4264 vs. 2164 RAM chips
Replies: 8
Views: 439

Re: 4264 vs. 2164 RAM chips

Hmmm, forgive my intrusion upon this learned discussion, but I think you can just pop in a 41256 chip in lieu of a 4164 and it should work as a 64k chip. The C64 will simply never address the extra memory. The extra A8 line on the 41256 would be left floating, so you'd need to tie it to a low-impeda...
by Gyro Gearloose
Sat Mar 23, 2019 10:23 pm
Forum: Hardware
Topic: Is the SX-64 motherboard identical to the standard C64?
Replies: 8
Views: 453

Re: Is the SX-64 motherboard identical to the standard C64?

Oooh the 1902 monitor had an 8 pin DIN input for the 128's RGBI output. So that's two places you could plug the wrong cable to.
by Gyro Gearloose
Sat Mar 23, 2019 1:24 am
Forum: Hardware
Topic: Is the SX-64 motherboard identical to the standard C64?
Replies: 8
Views: 453

Re: Is the SX-64 motherboard identical to the standard C64?

I know it's been 7 days since the last post on this thread, but I'm wondering what connector an RGB monitor cable would plug into. I wondered about that, I think the Amiga had a RGB cable that went from the Amiga's DB-23 to a DIN 6 connector on the monitor. https://www.ebay.com/itm/OEM-COMMODORE-Am...
by Gyro Gearloose
Sat Mar 16, 2019 3:25 am
Forum: Hardware
Topic: Is the SX-64 motherboard identical to the standard C64?
Replies: 8
Views: 453

Re: Is the SX-64 motherboard identical to the standard C64?

It's not even "a" motherboard, it's a few separate boards that plug into each other, and sections of it are not even like the regular 64.
Why do you think troubleshooting it would be that hard?
by Gyro Gearloose
Fri Mar 08, 2019 4:29 am
Forum: Other 8 bit Madness
Topic: Suggestions on Plus 4 problem?
Replies: 16
Views: 1405

Re: Suggestions on Plus 4 problem?

update: I ordered some 74LS257 parts from Futurlec and they also fail in the same way, one out of 4 logic units fail, all the same.
guess I can't cheap out on these.
by Gyro Gearloose
Tue Feb 19, 2019 3:54 am
Forum: Other 8 bit Madness
Topic: Suggestions on Plus 4 problem?
Replies: 16
Views: 1405

Re: Suggestions on Plus 4 problem?

Well there we go. I received my device programmer, the TL866, and it has a logic IC test function. https://i.postimg.cc/XqWhZbCQ/failed257.jpg There's the problem with the 8708. Honestly I bought that programmer since it was recommended over at EEVBlog, I didn't check all its features. I was pretty ...
by Gyro Gearloose
Mon Feb 18, 2019 3:44 am
Forum: Other 8 bit Madness
Topic: Suggestions on Plus 4 problem?
Replies: 16
Views: 1405

Re: Suggestions on Plus 4 problem?

I tossed in a 157 instead of a 257 and now I have the full 60K free on power up. The 257 has three-state outputs but in the Plus 4 the OE is always low so the hi-z output is never even used so a 157 does the job. It's been a long time since I fooled around with discrete logic... But I got it to work...
by Gyro Gearloose
Sat Feb 16, 2019 5:14 pm
Forum: Other 8 bit Madness
Topic: Suggestions on Plus 4 problem?
Replies: 16
Views: 1405

Re: Suggestions on Plus 4 problem?

I'll hook up the 8708 chips on a breadboard and take a look at how they work or rather don't work. My place is a mess, so later. In the meantime I noticed I was actually missing a lot of 74LS parts used in C= machines so I ordered a bunch from Futurlec. I don't know about buying 74LS parts on eBay. ...
by Gyro Gearloose
Fri Feb 15, 2019 5:32 am
Forum: Other 8 bit Madness
Topic: Suggestions on Plus 4 problem?
Replies: 16
Views: 1405

Re: Suggestions on Plus 4 problem?

Well it amuses me to no end that I can get TTL chips from behind the Iron Curtain! https://www.ebay.ca/itm/K555KP11-SN74LS257-SN74LS257N-IC-Microchip-USSR-Lot-of-2-pcs/132772129132?hash=item1ee9d5e96c:g:gpIAAOxydB1Sm~rh:rk:29:pf:0 LOL I'm going to give these a try. They'll probably be on 2.5mm cente...