Thanks Runrin, I was pretty happy with how the Pi Zero version turned out. I've had this setup in some form or another for several years. The original version of this was on a larger raspberry pi so I have used USB to serial adapters without issues. Initially the Zero was run off of a USB to serial adapter as well until one day I thought I might be able to stuff a MAX232 inside the tiny case with a bulkhead mount RS323 and it worked. So presently you can use my Zero on the M100 either via ttyUSB0 or ttyS0. Results are the same. I do recommend using a FT232RL based converter or an authentic Prolific PL2303 if you can find it. That way you know you are getting something with correct voltage levels.
Brian On Tue, Dec 12, 2023 at 8:13 PM runrin <run....@rin.run> wrote: > Wow Brian! > > This setup with the Pi attached to the back looks amazing. It's attached > so cleanly as well. I appreciate you doing the `stty' at the end, > hopefully mirroring your setup will help me get things working better on > my end. > > I do wonder if the fact that you are using the Pi's GPIO pins to do > serial instead of a USB adapter is part of why your system is working so > well. If you have a USB adapter floating around, I'd be really curious > if you got the same results with that connected to the PI instead of > connecting it directly. > > Thanks again for sharing your experience getting this working. > > On Tue, Dec 12, 2023 at 05:42:28PM -0500, Brian Brindle wrote: > > This has come up in discussion a few times so I wanted to show that > > 19.2Kbps on the Tandy 100 is possible with only software flow control. > > > > Here is a video of me creating a 500 line 40 col file that is 20KB, > > transferring it to the M102 and back again using the 19.2Kbps serial > > connection. It gets slowed down due to the screen being so slow making > > it absolutely of no value to be running at those speeds but does > > demonstrate that flow control can be used on a Linux device in this > > situation. > > > > Hardware flow control would work best and is what I would recommend > but > > I wanted a device that would work on a stock M100/102 and on a M200 > > where the flow control lines do not work properly. > > > > It's apparently really hard to film, type and remember what to say so > I > > apologize for that.. > > > > [1]https://youtu.be/BGxx__Zr1O4 > > > > Brian > > > > References > > > > 1. https://youtu.be/BGxx__Zr1O4 >
