Model II - Kermit and file transfers

[dhoelzer]

I'd really like to cross post this to the CP/M forum as well, but I can't see a way to do it. I wanted to share my success and document it for future experimenters. My Model II is not only up and running but I now have a fully functional Kermit 4.11 and Z80 assembler on it!

To get this done you must first get your hands on a working Pickles & Trout CP/M boot disk. If you are trying to get a Model II, 12, 16 up and running and do not have a working P&T, I'm more than happy to make you one if you send me a couple of blank 8" floppies (send a couple in case there are bad sectors on the first one!). Just PM me.

With this prerequisite:

1. Get the GNU Screen utility installed on your Linux, BSD or Mac computer. http://www.gnu.org/software/screen/
2. Connect your computer to the Model II Serial port A (the top port) using a null model cable. If you're in USB land (like we all are these days), I've found the Gold-X USB-Serial to be very reliable. (Look for part number GXMU-1200) (please note that this is just a serial connector... you will still need a null modem as well!)
3. Assuming that you have done these first two steps, fire up screen connected to your serial connection: screen /dev/tty.usbserial 9600 <-- Of course, your device may be differently named, especially on Linux. Check out the USB devices available in /dev.
4. The last command will connect Screen to your serial connector at 9600 baud, the default for the Model II. You are almost ready to go!
5. Go and grab the CP/M Kermit distribution: http://www.columbia.edu/kermit/cpm.html <- There are many download links if you just Google...
6. Locate the CPSKER.HEX file. The file is complete, but too large to send in one chunk. PIP will absolutely corrupt it when it tries to flush its buffer to the disk. To deal with this, assuming a UNIX command line (is there any other?), split -l 256 cpsker.hex
7. The 'split' command will have created 7 files named xaa through xag. Make sure that you have these files.
8. With these files in hand, first execute this command on the Model II: PIP 1.hex=RDR:
9. In your Screen window, hit CTRL-A:readreg p xaa <-- This is the exact character sequence. This will load the file 'xaa' into the 'p' register.
10. Screen should tell you that it has slurped in stuff. Now hit CTRL-A: paste p <--- There's actually no space between the colon and the 'p' but it keeps putting a smiley in in the forum post!
11. You should see your serial lights flickering (provided that you have some!). You can either wait until the lights stop flickering or just wait a few seconds and then hit CTRL-Z. You will know that the transfer is complete when you see your floppy drive light come on, it writes the data and then returns to CP/M.
12. Repeat these last few steps for each file from 'xaa' through 'xag' coupled with the PIP command creating files 1.hex through 7.hex. Don't forget to start the PIP first!!
13. If you inadvertently type a couple of characters into the screen window, make note of which file you did it with. When you're all through getting the files, just open that file up in VEDIT and remove the offending characters.
14. Locate the file CPVTPT.HEX.
15. On the Model II, type PIP CPVTPT.HEX=RDR:
16. In screen, use 'readreg' to read in the CPVTPT.HEX file and then 'paste p' to send the file. Control-Z at the end as usual.
17. You now have all of the data in place. We need to rebuild CPSKER.HEX. Type: PIP CPSKER.HEX=1.hex,2.hex,3.hex,4.hex,5.hex,6.hex,7.hex <--- After you hit enter, SIT ON YOUR HANDS!!! If you start typing you will abort the copy.
18. When you are returned to a command prompt, type DDT CPSKER.HEX
19. Wait.
20. When DDT is ready, type: icpvtpt.hex
21. After hitting enter, type the single character 'r' and press enter again. Wait (this will be fast).
22. Hit Control-C
23. At the CP/M prompt type: SAVE 116 KERMIT11.COM

That's it! You now have a working Kermit ready to transfer files.

Enjoy!