Okimate 20

Just for fun I thought I'd have a go at trying to render output from the Amiga Okimate 20 printer driver. This printer is a strange beast. Apparently, you issue ESC CHR(25) commands to reset the color to yellow, and then after you issue a CR it changes the color and prints in magenta, issue another CR and it switches to cyan. After those 3 passes you issue CR LF and then do a ESC CHR(25) again to restart the process.

It has a horizontal graphics resolution of 120 dpi for 960 pixels across. It has a 24 pin mode to print 24 pixel strips.

ESC % O puts you into graphics mode and then byte0 and byte1 for the number of horiz pixels (byte0 + byte1*256). Following this you have 3 bytes for each 24 dot vertical pixel strip.

I can feel the virtual thermal ribbons burning a hole in my virtual pocketbook as it renders the prints. Goodness, they must have been expensive to print full page graphics. 3 pages must have about wiped out a single ribbon. Reminds me of my old Casiowriter thermal typewriter that had these film ribbon cartridges that would be good for about 10 pages.

If you're curious I got the information about the printer from:

http://www.myokidata.com/om20ibm.nsf/InsideUsersManual

I think I only implemented 3 codes: ESC CHR(25), ESC %O, and ESC J (advance n/216).

All the ESC programming codes are nicely summarized on this page:

http://www.myokidata.com/om20ibm.nsf/MOCContents/F5982DA819FFFAAF8525634800547D3D?OpenDocument





Okimate 20 javascript interpreter