Using Kermit on the Commodore 900

Running Kermit on the Commodore 900 is a bit awkward but it works.  I have used it to send and receive files between a PC laptop and the C900.  For my scenario, I use an old laptop with a proper 25 pin serial connector on COM1.  I have an old laptop for stuff like this.  I tried a USB to Serial and I had issues so I just went this way and it was simpler. I use a 25 pin “straight thru”  serial cable for communication.

I use MS-DOS Kermit 3.15 on the laptop and use the stock Kermit on the Commodore 900.   On the C900 I connect to “RS232 Line 2” and NOT “Line 1” as this is used by the C900 for debug information on boot up and when I switched to Line 2 and all was well.

So, the initial set up:

1. On the Commodore 900, connect the 25 pin serial cable to “RS232 Line 2”
2. On the laptop, connect the 25 pin serial cable to COM1.
3. Load PC Kermit on the laptop.
4. Run the following commands to set up PC Kermit (some are probably not needed but I do them anyway)
   • SET PORT COM1
   • SET SPEED 9600
   • SET PARITY NONE
   • SET DUPLEX FULL
   • SET FLOW-CONTROL NONE
   • SET FILE TYPE BINARY

To send or receive files, you need to start up the Kermit console on the C900.  Because that is a constantly running process, you need to “break out” and then run the appropriate send or receive command.  Please note:  to break out of the Kermit console, you need to do a <shift> 6, then hit “s”.  To explain this, the <shift> 6 = the caret symbol (^) and sending a “s” is to suspend the console.  Two key hits one after another. (shift-6 = one key hit, then “s” is the other).

Receive a file on the C900 from the PC:

1. On the PC, run Kermit and do the initial set up commands above.  You will be in the Kermit console on the PC when you do this.
2. On the C900 you also need to run the Kermit console.   Log into the C900 as “root”.  This sets the pathing so Kermit can be found and you can run it from whatever directory you want to send files from or receive files in.
   • kermit cilb /dev/tty51 9600  <enter>   (Kermit console will start and you can’t get out)
   • <shift> 6, then “s”    (break out of Kermit console)
   • kermit rilb /dev/tty51 9600 <enter>  (This is the “receive” command.  C900 Kermit is now waiting for you to send a file from the PC)
3. From the PC Kermit console
   1. s filename   (This is the “send” command.  You can use a path in the filename)
4. File transfer will commence
5. To send another file, you do not need to run the Kermit console on the C900 as it is already running.  Just run the “receive” command. Note, if a certain time elapses, you may have to run the Kermit console command again.

Send a file from the C900 to the PC:

1. On the PC, run Kermit and do the initial set up commands above.  You will be in the Kermit console on the PC when you do this.
2. On the C900 start the Kermit console, then send the file:
   • kermit cilb /dev/tty51 9600  <enter>   (Kermit console will start and you can’t get out)
   • <shift> 6, then “s”    (break out of Kermit console)
   • kermit silb /dev/tty51 9600 filename <enter>  (This is the “send” command.  C900 Kermit is now waiting for you to tell the PC to receive the file)
3. From the PC Kermit console
   1. r    (This is the “receive” command.)
4. File transfer will commence
5. To send another file from the C900, you do not need to run the Kermit console on the C900 as it is already running.  Just run the “send” command.  Note, if a certain time elapses, you may have to run the Kermit console command again.