Search found 705 matches

by bwinkel67
Fri Jul 02, 2021 5:22 am
Forum: Hardware
Topic: QL-VGA v2
Replies: 67
Views: 5127

Re: QL-VGA v2

varmfskii wrote: It didn't seem to change anything. BTW looking at the plans for the QL, it has what I believe is the main crystal as 15 MHz. Is this accurate. The crystals on mine seem to be different. The main crystal being 15.10489 MHz.


So the VGA issue was still there after you removed the board?
by bwinkel67
Thu Jul 01, 2021 8:54 am
Forum: Hardware
Topic: QL-VGA v2
Replies: 67
Views: 5127

Re: QL-VGA v2

mk79 wrote:Without access to such a machine it's basically impossible for me to develop for it.


Dave just bought a working US QL, maybe you can work with him to see if he can figure out what's going on.
by bwinkel67
Wed Jun 30, 2021 11:52 am
Forum: Hardware
Topic: QL-VGA v2
Replies: 67
Views: 5127

Re: QL-VGA v2

That's what my board looks like...crazy US motherboards. I'm assuming this all had to do with FCC regulations?!?

Edit: Well, my RAM chips don't have those resistors across them...
by bwinkel67
Tue Jun 29, 2021 11:30 pm
Forum: Hardware
Topic: Mechanical "membrane"
Replies: 2
Views: 194

Re: Mechanical "membrane"

Someone on the forum was working on something similar. The issue, I think, is that those switches won't feel very responsive and/or last too long. The real issue is the way the keys are done themselves. I think Tedroid had actually shown a complete replacement were the top of the case had to be cut ...
by bwinkel67
Tue Jun 29, 2021 8:45 pm
Forum: Software & Programming
Topic: Digital C code gen
Replies: 9
Views: 571

Re: Digital C code gen

Wow, lots of resources available. I had the Hendrix book back in the day...haven't looked at it in a long time but it is still sitting on my shelf.
by bwinkel67
Sun Jun 27, 2021 11:13 am
Forum: Software & Programming
Topic: Digital C code gen
Replies: 9
Views: 571

Re: Digital C code gen

Well, the source code is available if you feel like digging more into the code generator. See Dilwn's page to find it. Tim I've looked at it...it's not the easiest to understand. I do have Hendrix book on Small C so I should take a look at it as it may do a better job since it does come with source...
by bwinkel67
Fri Jun 25, 2021 5:19 am
Forum: Software & Programming
Topic: Digital C code gen
Replies: 9
Views: 571

Digital C code gen

Been playing around with Digital C 'SE' to see how well it does code generation. Already known of a few cases where it isn't optimal: ⋅  the while loop in same form as for loop generates smaller code: i.e. for (i=0; i<10; i++) { } not same code size as i=0; while (i<10) { i++; } ⋅&nbs...
by bwinkel67
Sat Jun 19, 2021 4:52 am
Forum: Hardware
Topic: Microdrive data line format
Replies: 65
Views: 30997

Re: Microdrive data line format

Finally in 2017, after several PCB revisions, and once the manuals and install guides had been done, I thought I'd make a couple for enthusiasts :-) As it turned out, I had significantly underestimated the demand and with the continued interest, I'm still making both the ZX and QL vDrives today (ht...
by bwinkel67
Sat Jun 12, 2021 11:26 pm
Forum: Wanted
Topic: QL PCB
Replies: 2
Views: 330

Re: QL PCB

I'm surprised you haven't gotten a response yet on your original post. Usually it's a bad chip that causes that, not a bad motherboard. Unfortunately I don't have enough experience with failures to give any insights. But best bet is to go to sellmyretro and buy a few replacement chips first (like th...
by bwinkel67
Thu Jun 10, 2021 11:31 pm
Forum: Hardware
Topic: GermanQL and composite signal
Replies: 2
Views: 243

Re: GermanQL and composite signal

I don't know about the German models but the US ones only have monochrome composite out on the RGB DIN socket. Note that both US and German models also use DB-9 serial and joystick connector. Pin 1 on the RGB socket gives a 5 volt signal and no composite color out. Now it's easy enough to fix since ...