Sidenote: For wonks who want to check my numbers, the file was 16197 bytes long. For effective bps, I used 10 bits per byte because I don't recall exactly how all the stop bits and parity add up, but I know it is more than 8 bits. I did the timing by typing ?TIME$: LOAD... and then, once that was started, typed ?TIME$ and hit ENTER so that it'd show up as soon as the loading was finished. On the PC end, I used my other hand to hit ENTER a fraction of a second after I hit ENTER to start the LOAD on the Tandy 200.
On Tue, Nov 1, 2022 at 10:58 AM B 9 <hacke...@gmail.com> wrote: > Good question. I know that 19,200 makes a substantial qualitative > difference compared to 9600 when using TELCOM to connect to a UNIX shell. > For loading BASIC programs, I don't know that it would make a difference as > I usually just let it run and forget about it while it tokenizes.I only > mentioned loading from BASIC because that was the lowest maximum download > speed in your table (600 baud). > > Timing test for a 16K BASIC (in ASCII) sent to a Tandy 200: > > > > Command Bits per > second > Time Effective > bps > LOAD "COM:98N1ENN" 19200 58s 2793 > LOAD "COM:88N1ENN" 9600 59s 2745 > LOAD "COM:68N1ENN" 2400 78s 2076 > LOAD "COM:48N1ENN" 600 270s 600 > > So, as Mike predicted, there is no difference between 9600 and 19,200. > What was interesting to me was that, although those rates are able to go > faster than 2400 bps on average, when the connection speed is 2400, the > effective rate is lower. That shows that the tokenization speed on my Tandy > 200 varies. It is rarely faster than 9600 but it is sometimes slower than > 2400, which is probably why Mike suggested 600 as a safe maximum speed. > And, sure enough, when I try 600 bps, the BASIC tokenizer is able to keep > up perfectly without ever having to send XOFF to pause the transmission. > > This also shows that any PC serial port that is able to send a BASIC file > at 9600 has to have XOFF/XON working well. While it is not conclusive, I > would guess that the same connection would work fine at 19,200. > > —b9 > > > > On Tue, Nov 1, 2022 at 8:57 AM MikeS <dm...@torfree.net> wrote: > >> Maybe I should have said that XON/XOFF is hit-and-miss depending on the >> hardware instead of 'unreliable' ;-) . >> >> It's not always easy to know whether a particular setup will work or >> not; I've seen USB cables recommended that I couldn't get to work and, >> conversely, had no problems with others that supposedly did not. >> >> FWIW, I normally also run at 19200bd but thought it would be safer to >> recommend 9600 bd in this discussion since it usually works no matter what >> and makes very little difference in actual throughput. >> >> Have you ever compared actual BASIC download speed at 9600 vs. 19200bd? >> >> m >> >> >> ----- Original Message ----- >> *From:* B 9 <hacke...@gmail.com> >> *To:* m...@bitchin100.com >> *Sent:* Tuesday, November 01, 2022 3:33 AM >> *Subject:* Re: [M100] Notoriously S.L.O.W BASIC posted - help speeding >> it up appreciated >> >> >> On Mon, Oct 31, 2022 at 12:11 AM MikeS <dm...@torfree.net> wrote: >> >>> Reliable maximum download speeds on the M100 without handshaking are >>> around: >>> BASIC: 600 bd to allow time to tokenize and store. >>> TERM: 2400 because of the slow LCD scrolling. >>> TEXT: 9600 since it does not display while loading. >>> >> >> That sounds right when the other end does not have hardware-level >> XON/XOFF, but it should be much faster with a better UART on the PC, like >> an OX16C950 >> <https://pdf1.alldatasheet.com/datasheet-pdf/download/161698/OXFORD/OX16C950.html> >> or a chip from FTDI or MOXA. As soon as the M100 sends XOFF, the UART chip >> in the serial port automatically stops the flow of data. No lag, no lost >> characters. I connect using 19,200 bps in BASIC (*LOAD "COM:98N1ENN"* ) >> and it works perfectly when I use certain USB serial adapters (and not >> others). >> >> Has anyone with a Model 100 tried using a serial card or USB adapter that >> supports "automated in-band flow-control"? Do you see the same high-speed >> connection as I do on my Tandy 200? >> >> —b9 >> >>
