| ??? 05/14/09 14:24 Read: times |
#165336 - I'm not so sure ... Responding to: ???'s previous message |
Per Westermark said:
Many small dot-matrix ribbon printers may not have any formatting at all and just expect raw graphics data, and direct motor drive commands to step the paper forward. They are also often sold as just the mechanics, since they are intended to be integrated with other electronics - maybe a card reader, or a keypad and display or similar. While it's quite easy to believe that such things existed, I, personally, in well over 30 years in the industry, have never seen one. I have seen small dot-matrix printers that had a graphics mode, but never one that only operated at low-level, yet had the "standard" Centronics parallel interface that was most common on such printers. When that Centronics connector appears on the printer, I am comfortable assuming that it adheres to the basic Centronics operating protocol. After all, the Centronics interface was VERY common before IBM woke up and ventured into the microcomputer industry. Only Apple Computer Co. tried to build printers that used the microcomputer system to do the low-level intelligence to run the printer, just as they did with their floppy disks. It really is important to know what printer - after all, dot matrix printers have died away for most uses right now. Being impact printers, their strength may be to emit multi-part forms, or as an alternative when you need an archive classification from a ribbon printer. The thermal prints are so sensitive to sunlight or mechanical abuse. If the O/P has a printer that bears the 36-contact Centronics connector on the chassis, I'd bet he can use the standard Centronics (not the IBM-PC version) interface to drive it. BTW, there were "ribbon" or "band" printers that were a special class of printer (relatively high speed) and were not in the same "league" with typical character-by-character dot-matrix or daisywheel printers that printed a single character at a time. These relied on multiple print hammers and a rapidly circulating "ribbon" or "band" on which the character impressions were placed, and timing the hammers was the key to their operation. This mechanism was common in so-called "line-printers". When programming in FORTRAN, it was not unusual for students to make the mistake of placing the wrong control character in the first position on a Hollerith card, thereby causing the printer to "stack paper on the ceiling" because it executed form-feed with each character, and could, indeed, execute a FF, LF, or CR in the same time as it took to print any other character. Computer-room technicians didn't like it when it happened, as what goes up must come down, and they had to clean it up. There were, generally speaking, not graphics-capable, though I did once own one that was graphics-capable if one used only the period or asterisk to draw the graphic. It would be good not to mix the nomenclature. RE |
| Topic | Author | Date |
| Dot Matric Printer driver with 8051 | 01/01/70 00:00 | |
| DMAP? | 01/01/70 00:00 | |
| there is no such thing | 01/01/70 00:00 | |
| Normally quite straight-forward | 01/01/70 00:00 | |
| Interfacing Printer | 01/01/70 00:00 | |
| Not a safe assumption | 01/01/70 00:00 | |
| ribbon printers can have very raw interface | 01/01/70 00:00 | |
| I'm not so sure ... | 01/01/70 00:00 | |
| Printing _on_ ribbons | 01/01/70 00:00 | |
RE: OP has never mentioned any interface | 01/01/70 00:00 | |
| Definately | 01/01/70 00:00 |