Interrupt-Driven Terminal Emulator

[glitch]

I currently use Kermit-80 to transfer files between my Linux machine and my Kaypro II. I've used Kermit under DOS, so I'm familiar with its commands; however, it drops characters when used as a terminal emulator. I've read a bit on the problem and it seems it's a function of the Kaypro's slow internal display update, but that this can be solved by using a terminal emulator that's interrupt-driven rather than polled. Does anyone have recommendations for such an emulator?

 

[glitch]

Well, I've tried several different terminal emulators with some mixed results:

Kermit-80: Drops characters like crazy...least effective
TERM.COM: the ADM-3 emulator that comes with the Kaypro II...better than Kermit-80, but still drops
MEX: Modem EXecutive...slightly better than TERM.COM, but still drops some characters
MITE: Slightly better than Kermit-80, but not by much

My tests are based on direct-connect usage as a dumb terminal with the Ohio Scientific, running at 9600 baud. From what I'd read, I would have expected MITE to have preformed a lot better than it did...perhaps I failed to enable interrupts properly? Any further insight would be appreciated.

In searching for a program that'd work for me, I came across mention of a program called INTTERM which is apparently written for the Kaypro using interrupts. I haven't been able to find a copy, but research suggests it was available through SIMTEL20 or Micro Cornucopia -- if anyone has a copy, I'd love to get one!

 

[ahm]

It would be useful to know your serial port speed.
Perhaps it's actually your UART struggling to keep up, not the software.

 

[glitch]

It would be useful to know your serial port speed.
Perhaps it's actually your UART struggling to keep up, not the software.

Actually, it seems it's the Kaypro's display firmware that can't keep up. The UART is supposed to be able to do 19200 baud, and works fine at that speed when doing file transfers (I regularly use Kermit-80 to transmit files between the Kaypro and my Linux desktop). From archived news threads, I've been able to gather the problem can be avoided by using interrupts rather than polling -- people have reported being able to use a Kaypro as a dumb terminal at 9600 baud with no drops. Of course, if nothing else works, I can probably try out one of the enhanced Kaypro ROMs.

 

[Chuck(G)]

Have you looked at FASTTERM for the Kaypro? One of your issues may not be the comm servicing, but rather the slowness of the video display code.

 

[glitch]

Have you looked at FASTTERM for the Kaypro? One of your issues may not be the comm servicing, but rather the slowness of the video display code.

I downloaded/transferred FASTTERM, but on trying to run it, the Kaypro restarted with a warm boot directly. I did find a library file in the Walnut Creek archive claiming to be an add-on/improvement patch for INTTERM/FASTTERM, so I'm going to try applying that.

 

[glitch]

I just found a copy of INTTERM! The archive KPNEWTRM.LBR contains INTTERM, the patches, and a file called NEWTERM.COM with no documentation as to NEWTERM.COM's purpose. The particular copy of INTTERM found in the archive includes Micro Cornucopia fixes to improve its function.

EDIT: I finished looking over the Assembly source for INTTERM, and it looks like it will probably work with the Kaypro II. I was worried because it includes BAUDM in the archive, which suggested to me that perhaps it was for use only with two-port Kaypros. After consulting the technical manual, I found that all Kaypro models have a serial port available at 0x04 and control port at 0x06, which is what INTTERM uses.