Just noticed what the Z80 issue is. The chip you had from Aliexpress is not actually a Z80 CPU, it's a Z80 SIO chip which is a serial I/O chip. The Z80 can be tricky like that since all the chips are labelled Z80 (CPU, CTC, DMA, PIO, SIO), I've fallen into that trap myself. :)
Two thumbs up! The weird pin pitch of the keyboard connector stems from this connector having been an angled 25 pin D-sub for an external keyboard. The original C128 board was also used in the first edition of the 128D. That's also why you have two places for reset switches, with one being recessed, for the internal 1571 drive. And here I thought at first it would be a relatively normal pin pich that D-Sub used. *headscratch* Surprise, surprise. PS: I have a factory reject C128 board from a local store back then that has the 1571 reset switch populated from factory. ^.^ I suspect it was meant for the 128D!
Yeah I always took for granted that the dsub footprint was based on 2.54mm too but I guess its around 2.8ish. Totally get why they did it, just glad i was able to find a cheap and relatively painless workaround - Just a minor fingertip burn or two fiddling with all those little pins. :D
@@griffinretro if I had the proper crimp tool for dupont headers I would have made an adapter cable to go from the 128 keyboard to inline pins. The 2 by 2 pin header installation wasn't terrible though and it works pretty well even if a bit ugly. It's great that you added the headers to give us all options, you're awesome and I love this board!
The wiring for the Saruman 128 is different than in it's guide, why is that ? It's meant to mount in U53 isn't it ? is it different for the Neo, or does this just achieve the same result?
It kind of doesn't matter where exactly the board sits. As long as it hooks up to all 8 data bits it'll work all the same, the order really doesn't matter.
Yeah, comes with the territory I suppose. It's been a while since I bought them but I swear I ordered both from the same vendor. Guess they salt their inventory with junk chips too.
Running CPM on it will confirm the Z80 is working well.
Hi you just popped up on my page nice video’s will watch them all
Thanks for popping in, appreciate it!
Cool project - lots of stuff to solder but still
I love the smell of hot solder in the morning! :D
Just noticed what the Z80 issue is. The chip you had from Aliexpress is not actually a Z80 CPU, it's a Z80 SIO chip which is a serial I/O chip. The Z80 can be tricky like that since all the chips are labelled Z80 (CPU, CTC, DMA, PIO, SIO), I've fallen into that trap myself. :)
Oh wow, look at that. I had no idea. I'm glad I didn't bash the chip and toss it. It was sold to me as a CPU but I guess the seller got confused too.
Two thumbs up! The weird pin pitch of the keyboard connector stems from this connector having been an angled 25 pin D-sub for an external keyboard. The original C128 board was also used in the first edition of the 128D. That's also why you have two places for reset switches, with one being recessed, for the internal 1571 drive.
And here I thought at first it would be a relatively normal pin pich that D-Sub used. *headscratch* Surprise, surprise.
PS: I have a factory reject C128 board from a local store back then that has the 1571 reset switch populated from factory. ^.^ I suspect it was meant for the 128D!
Yeah I always took for granted that the dsub footprint was based on 2.54mm too but I guess its around 2.8ish. Totally get why they did it, just glad i was able to find a cheap and relatively painless workaround - Just a minor fingertip burn or two fiddling with all those little pins. :D
2.77 mm pitch for some reason. On the rev 4 board I added a 25 pin single row header for the keyboard since the connector is unobtanium.
@@griffinretro if I had the proper crimp tool for dupont headers I would have made an adapter cable to go from the 128 keyboard to inline pins. The 2 by 2 pin header installation wasn't terrible though and it works pretty well even if a bit ugly. It's great that you added the headers to give us all options, you're awesome and I love this board!
The wiring for the Saruman 128 is different than in it's guide, why is that ? It's meant to mount in U53 isn't it ? is it different for the Neo, or does this just achieve the same result?
It kind of doesn't matter where exactly the board sits. As long as it hooks up to all 8 data bits it'll work all the same, the order really doesn't matter.
Oh yes, recycled chips from Aliexpress sporting a fresh imprint😋
Yeah, comes with the territory I suppose. It's been a while since I bought them but I swear I ordered both from the same vendor. Guess they salt their inventory with junk chips too.