On Fri, Nov 11, 2022 at 11:12 AM John R. Hogerhuis <jho...@pobox.com> wrote:
> > So, it's not only been done, but you can poke the baud rate higher than > 19,200? > > Yes, as far as I know I was the first one to do anything with higher baud > rates. But I didn't come to the Model 100 scene until about 2004, I think. > > https://bitchin100.com/wiki/index.php?title=Model_100_Serial_Interface > That's an excellent page and contains all I need to use the higher speeds. It's a shame that BASIC is too slow for anything higher than 19,200. I wonder if it would help if the BASIC ROMs were patched to use hardware handshaking. Has anyone done that? [On a tangent: I need to work on my searching skills. It occurred to me a while ago that the Tandy 200 schematic looked like the RTS/CTS lines were fully wired, but when I searched for things like "model 100 serial port rts cts", I never saw that page... Oh! Wait. The problem may have been that I was googling with DuckDuckGo. I'm able to get bitchin100.com as the first result when I search for "model 100 uart", but only on Google.] And it is stable? >> > > At least on the Model 100 and T102 it is fine all the way up to 76800bps > Awesome. I think I should be able to connect at 76,800 on my PC since I've got GNU/Linux and I can set custom baud rates by dividing the serial card's base rate. I think my 16950 card's baud_base is 921600, so if I set the divisor to 12, I should get exactly 76800. (setserial /dev/ttyS0 spd_cust divisor 12.) > The possibility for the higher baud rates was clear from the UART data > sheet. https://bitchin100.com/wiki/images/2/22/6402.pdf > I think you probably are the discoverer of that, even if the Model T was over twenty years old when you started. I don't believe hobbyists had easy access to datasheets in the 1980s. I wonder when the last book for Model T tinkerers was published? So much new knowledge has been found since then. Wikis are great for looking up information, if you already know what you don't know, but they're not so great for giving a person new to a subject an idea of what is available and what is even important. It's hard to read through an entire wiki, or even to flip through one. By design, wikis are supposed to be quick to write, not well thought out or coherent. That's one reason I've more often turned to the Model T books and documentation instead of mailing list archives or wiki pages. While Tips, Peeks, and Pokes <https://archive.org/details/ProgrammingTipsPeeksAndPokesForTheTandyPortableComputers/> (Anderson, 1985) can't be said to be coherent, it is a carefully curated collection of short, non-obvious tips, expressed succinctly. I feel like a second volume of such tips could be created with everything that has be learned since 1985. For example, the ability to point a string to a memory address is a pretty neat trick, as is the ability to exceed the serial port speed limit. Also, some of the tricks could be updated. Just in my own research, I've found that I could expand on a few of Anderson's articles. For example, the PEEK to distinguish <https://archive.org/details/ProgrammingTipsPeeksAndPokesForTheTandyPortableComputers/page/n25/mode/1up> between a Model 100, Tandy 200, and Tandy 102 could also distinguish the Kyocera Kyotronic-85, the Olivetti M10 (Italy), the M10 (US), and the NEC family of portables. And Anderson's discussion of the RAM Directory <https://archive.org/details/ProgrammingTipsPeeksAndPokesForTheTandyPortableComputers/page/n43/mode/1up> describes the addresses of files in memory as only useful to assembly language programmers, but there are actually good use cases for accessing RAM files directly in BASIC using PEEK (fast, random access of binary data without needing a duplicate in RAM). Is the source code to TBACK.EXE available to learn from? >> > > No. HTERM source is available if you want to look at serial stuff. > I was actually wondering about how TBACK.EXE handles XON/XOFF. Does the program it sends to the Model T use hardware handshaking? Does it work with a Tandy 200 or only a Model 100? How does it configure the serial port on the PC side? There's a story docent told me... Frank Lloyd Wright designed walls at a > slight angle because he didn't like people hanging pictures on (his) walls. > The owners still figured out how to hang pictures. > > The idea with the one-liners being in PDF was to force you into the > enlightening joy of typing them in. They're short so it should be feasible > for most. > 😆 Ah! Well, I guess your gambit worked then. My OCR program was having fits over recognizing that dot matrix font, so I ended up just typing in the text by hand to create the PDF. And now I understand why I've been filled with enlightened joy of late. —b9
