Recent content by pjhacnau

For reference, my board(s) arrived today, should have it built in 2-3 weeks (spare time, what's that?) I'll let you know how it goes when set up. It's primarily for my M2 (fighting rolling problems on the driver board there) but I'll try it on my M4 as well.

The question is about the monitor you would connect to. The board we were discussing provides composite output so you would be plugging into the composite input of an external monitor. It might be worth looking at the service manual for the Model 2 - If I understand right the M2 video board...

One question - where are you in the world, and would you be working with NTSC or PAL? I raise this because I had a chat with the guy who made this board and he stopped producing its himself because it had issues when built for NTSC more often than not. (I'm demonstrating my lack of knowledge...

Hi all, I acquired a DSE System-80 (A.K.A PMC-80 or Video Genie) and it has (at least) one dead P2102 SRAM chip. Plenty seem available . . . from the other side of the world. So before I order some from (probably) the US, I wanted to check if anyone in Aus/NZ has some they are prepared to...

There's several forums I could ask this in but, given it occurred putting together a CP/M machine, I thought I'd ask here. I recently built one of the variants out there of Grant Searle's CPM machine - this one in particular (why that one? Someone not too far from me had spare boards they'd...

With a slight delay due to my hi-res board throwing a hissy-fit, I finally got my FreHD auto-boot setup going on the weekend. However there's a couple of "quirks" to resolve. One is with the date. Example from yesterday; (note SYSGEN has run VHDUTIL at this stage to pull the date and time...

Don't loose hope yet. That's the mess I made of the pads on my Model 1. All running again thanks to some extra wiring from the end of the lifted trace to the relevant pin.

Theoretical question at the moment but . . . one of these years I will get a CoCo (along with a whole lot of other things). Quite a few I see on eBay (at least in Aus) are the Color Basic versions. How hard is it to do an upgrade to ECB? A simple case of burning a ROM and swapping, or more...

My ultimate goal here is to restore an old AH game where the image on the 500-baud tape (from a still shrink-wrapped box) is bad. How bad? All the upward pulses are weak and some up/down pairs are completely below the 0 voltage. It's not too bad; only one block gives a checksum error (though...

I've had that problem too. May I suggest a "shrunk manual text correction device"? :cool:

Seems to be quite a few video questions ATM. I've just noticed this but I think it's been happening for a while. When the EI is connected to my M1, I get a moving pattern appearing - faintly - on the screen. The EI doesn't need to be turned on, just connected. (Turning on makes no difference...

Sorry if this has been covered, but a quick search didn't show anything up. So I've replaced the keyboard-mainboard connector, and cleaned the keyswitches which had decided to stop working on my M1, and put everything back together. The good bit - all keys work again. The bad bit - D works a...

Sigh. So I'm replacing the keyboard cable on my Model 1. I'll probably replace it with headers on each end but right now . . . the keyboard end is fine, but getting the cable off the motherboard end several pads, and 2 tracks, lifted. I'm less concerned about the two tracks - for pin 4...

If the kind people here will indulge me for a moment . . . 'twas Easter 1987 I became 100% sure I wanted to work with computers. I spent a solid 7 hours a day over the break working on a Uni programming assignment[1]. And enjoyed it the whole way. Add that to the mark I got and it said I...

Looking through TRS-80 books/articles/websites/... there seems to be a lot more information and analysis of the original 500 baud (OK, I'm ignoring the L1 300 baud here) cassette format than there is for the high speed "1500" baud format. I say "1500" as it isn't really. Given you have a single...