On Wed, Dec 21, 2022 at 10:34 PM B 9 <[email protected]> wrote: > On Wed, Dec 21, 2022 at 5:10 PM John R. Hogerhuis <[email protected]> > wrote: > >> Given that it wasn't actually using flow control I see no reason to make >> a simple 3 wire cable fail. It's punishingly opinionated. Sort of like >> Frank Lloyd Wright building interior walls at an angle because he didn't >> like people hanging pictures in the houses he made for them. >> > > Heh! I heard they hung pictures anyway. And, of course, I agree that > TELCOM shouldn't have cared about DSR unless it had a mighty good reason. > > Let's see if I got this right, > > Model 100: Ignores DSR > Tandy 200: Becomes punishingly opinionated about DSR > Tandy 102: Goes back to ignoring DSR > > Maybe someone at Microsoft was attempting to add flow control to the Tandy > 200 ROM and got it partially done before they had to ship. > > Does anyone know how to check the DSR register on the UART from BASIC? I > see something about I/O ports in the service manual > <https://archive.org/details/Model_200_Portable_Computer_Service_Manual_19xx_Tandy/page/n22/mode/1up?view=theater>, > but I'm not clear what port I should be reading or how. >
https://bitchin100.com/wiki/index.php?title=Model_100_Serial_Interface There's a I/O map at the end of the page. Did you mean Model 100/T102 or Tandy 200? There is an article on the wiki but I think it was copied from the Model 100 one as a starting point. Probably needs work. -- John.
