Posted on August 30, 2021
Quick Note on Tandy Video
The event of SepTandy is coming up in a couple of days. The focus for the month of September then are all things Tandy as one might guess or expect. I’ll be partaking in this with the one Tandy machine I have and I’m hoping to make the video the same quality as my MiSTer one so we will see if it turns out the way I have planned.
Capturing video from a Tandy 1000 machine is a little bit tricky to say the least. First off the video out port is 9 pins and it doesn’t support VGA at all. That wasn’t even a standard yet when the Tandy 1000 line launched so that is not an option. It basically outputs digital RGB which isn’t compatible with most capture solutions. You could drop in a VGA video card instead but then you lose out on all the great games offering TGA or Tandy Graphics Array mode.
Look at many games from the 80s and they will explicitly call that TGA mode out. A special 16 color mode only really available on Tandy computers of the era (PC Jr used a very similar setup being a direct competitor). Capturing this video raw has some challenges mentioned above. However I think I managed to sort that out.
What you are looking at is a raw capture from the video out port on a Tandy 1000 SL. It goes through a converter that changes the video signal to an analog RGB format a modern capture card can understand. As long as the card then can capture 15 kHz (as opposed to 30 kHz used by VGA) you are all set! This is mostly to support the video I’m working on but this also opens up the door to streaming with this Tandy machine with little extra setup so look to that happening as well.
The adapter in question being used for the conversion can be found here: CGA2RGBv2. My Datapath E1 card I use for most retro captures supports 15 kHz natively so that makes that part easy. Below is a video capture test I performed as well.