Oh, I didn't realize that they had extended CGA that much. Cool.
Oh, I didn't realize that they had extended CGA that much. Cool.
It's basically IBM PCjr graphics but known to most as TGA. This is because the Tandy 1000 line was so successful and the PCjr died such a quick death. On the EX you had to have 384kb of ram or more to use the mode but for most games (eg from Sierra etc) there was no practical difference between EGA and CGA on an XT (other than 16 colours only being available at 320x200 vs 640x350 for EGA).
there a good Wiki on TGA here:
https://en.wikipedia.org/wiki/Tandy_Graphics_Adapter
I'd be interested in one of these boards if you end up making them. Also, do you have a part list link for the cable you made?
I'd be interested in one of these boards if you end up making them. Also, do you have a part list link for the cable you made?
Cheers, once I've finished building my last two isa IDE boards (seriously time poor atm) I'll finish of the design. Would you find the 1:1 plus-isa adaptor more useful than a 1:2 plus-isa adaptor?
As for the ribbon cable version, I bought all the parts from Vetco. They have the 62 pin idc female headers but not 62 pin edge connectors so I used the 64 pin versions and bought and trimmed 64 wire ribbon cable also.
Female header (not keyed, ignore the picture):
https://vetco.net/products/62-pin-idc-female-socket-connector-0-1Edge connector:
https://vetco.net/products/64-pin-card-edge-female-connector
Would you find the 1:1 plus-isa adaptor more useful than a 1:2 plus-isa adaptor?
That's a good question. I'm guessing 1:1 as hopefully I'll find a plus serial adapter out there and will only need it for the ide interface. It has been a lot of fun "playing" with the first ever PC I owned 30+ years ago.
I still need to find the 3.5 inch external drive. I had one with my original PC, but haven't been able to find one now. If only I had kept it all.
Would you find the 1:1 plus-isa adaptor more useful than a 1:2 plus-isa adaptor?
That's a good question. I'm guessing 1:1 as hopefully I'll find a plus serial adapter out there and will only need it for the ide interface. It has been a lot of fun "playing" with the first ever PC I owned 30+ years ago.
I still need to find the 3.5 inch external drive. I had one with my original PC, but haven't been able to find one now. If only I had kept it all.
Cool, I think the 1:1 is the go also as it allows for mixing and matching of plus and isa boards.
The external drives do pop up on eBay occasionally (i bagged the last one to appear) we never had the external drive for ours but we did have the ram expansion and serial card which we used for a real mouse. The Tandy mouse that was available for use in the joystick ports was pretty crap as the pots had finite range of movement.
Where'd you source the 62 conductor ribbon cable?
Where'd you source the 62 conductor ribbon cable?
I didn't, I got 64 wire ribbon cable from Vetco and removed 2 wires.
That's what I thought. One more question. Since you used the Lo-Tech card, which way does it go in? I'm un-sure with regards to front and back of a standard PC, which is PIN 1. Hope the question makes sense. I don't want to insert it backwards.
That's what I thought. One more question. Since you used the Lo-Tech card, which way does it go in? I'm un-sure with regards to front and back of a standard PC, which is PIN 1. Hope the question makes sense. I don't want to insert it backwards.
So I deliberately use the Red Stripe at the end which will be closest to the back of the case and with the ISA-CF-IDE card the IDE header end of the card is the back - meaning it is closest to the rear of the case also. I made sure the red stripe of ribbon cable was installed at the end of the connector also. This will be Pin 1 for both connectors. See pic below:
This should work as shown but I havent been able to test it myself as my 1000 EX hasnt arrived yet. The EEPROM chips used in these are quite "fragile" and will die if the board is in the wrong way (the other chips wont care). So the easy test is to remove the EEPROM chip and see if the machine boots ok without it. if the board is in the wrong way you'll likely get some weirdness or errors - otherwise the Tandy should work just fine as tho the board isnt there.
btw, use a bench vice or large clamp to "install" the ribbon cables into the IDC termination block as they need a fair bit of pressure to install properly. Just dont go all in, ease on the force until it's really well terminated and the clamp part of the termination block sits nice and flat by itself.
Make sure you orient the cable as shown below - ie coming out of the PLUS Female header towards the ISA Slot, looping back over away from the ISA Slot and then coming top down into the ISA slot with the back 2 pins (end furthest away from red stripe) not connected. I'm 99% sure this will work as i've mapped it out in my head - it's copied from a couple of video's I've seen of similar adaptors so im fairly confident in the implementation.
Thanks a bunch. I should have all my stuff in a week or so. We'll see how it goes.
Thanks a bunch. I should have all my stuff in a week or so. We'll see how it goes.
No worries. Btw I updated my post above with extra info.
Haha, thanks! Maybe I'll let you try it first and if it works, you can post a pic all installed.
Haha, thanks! Maybe I'll let you try it first and if it works, you can post a pic all installed.
Awesome - TBH I'd try an old ISA serial card, with a serial mouse, first to ensure the apdator works (this is my plan).
PS I'm happy for other 1000 owners to post here with pic's etc.
I just finished an adaptor board design in Diptrace for Tandy 1000 external floppy drives (the cables cant be made easily as 30pin IDC Edge connectors as extinct) and placed the Order with Elecrow - should be an interesting trial run for the riser design:
So I think I've finished the adapter design - im not going to get it made just yet, I'll prolly wait till I can test some printed paper models first:
Just waiting on the PCB's now. :cool:
and my 1000 EX is due next week now, so hopefully I'll be ordering the PLUS-ISA PCB's soon too.
Huzzah, my Tandy 3.5" drive and the Adapter PCB's both arrived today and the adaptors will work and fit perfectly!
Just waiting on my 1000 EX now.
PS, Im quite happy with the quality of the Elecrow PCB's and the price was great (10 boards for ~18 AUD).
That's a major milestone. Congrats, djos!
That's a major milestone. Congrats, djos!
Cheers, gives me confidence that the PLUS to ISA adapter will work too. I'll actually have to start designing some more complex designs next.