Tuesday, October 30, 2012

Super Forth 64 - RS 232 console.


Today I managed to connect to my C64 running Super Forth 64 from a PC computer via RS-232 with Hyper Terminal program.

To do so, first we need to open logical file to user port's RS-232:

10 2 10 " {CTRL-H}" OPEN

NOTE: CTRL-H represents code CHR$(8) which sets the speed of RS-232 interface to 1200 baud. To connect with 300 baud, use CTRL-F (CHR$(6)).

Assuming that PC computer is connected to C64's user port via RS-232's COM1 and that C64's user port is equipped with appropriate interface, on the PC side, open Hyper Terminal session to COM1 at 1200 baud 8N1.

After opening logical file, we need to redirect I/O to that file. On the C64 side type:

10 OUTLFN !
10 INPLFN !

NOTE: After output redirection (typing in 1st line above and pressing Return), C64 console will no longer show output. Instead it now should appear on the Hyper Terminal's screen. After entering 2nd line, enable CAPS-LOCK on the PC and perform all FORTH session interaction from Hyper Terminal (HT) from now on. 

Commodore 64 is now a Super Forth 64 host, and PC with HT is a client session. Not all operations are possible via such session. E.g: user will be unable to use screen editing facility. Also, character codes are not fully compatible between PC and C64, so all C64 responses will be in capital letters. If there is any text using mixed caps coming from C64, the letters that'd be visible as capital letters on C64 will not come right on the HT side. 

C64 screen after redirection to RS-232 just sits quietly while interaction is performed from HT on a PC.
HT/PC side.

Thanks for visiting my blog.

Marek Karcz
10/30/2012