The Line Printer Port
MIRE includes a line printer port that is functionally identical to the one in the original Expansion Interface. It has been slightly modernized by using a 25-pin D-SUB connector which is wired like a Standard Parallel Port (SPP) on a PC.
The MIRE PCB has a site for an optional 26-pin header which compatible with the usual pinout of PC motherboard LPT connectors:
| DB-25 Pin | Header Pin | SPP Signal |
|---|---|---|
| 1 | 1 | -STROBE |
| 2 | 3 | D0 |
| 3 | 5 | D1 |
| 4 | 7 | D2 |
| 5 | 9 | D3 |
| 6 | 11 | D4 |
| 7 | 13 | D5 |
| 8 | 15 | D6 |
| 9 | 17 | D7 |
| 10 | 19 | -ACK (unused by MIRE) |
| 11 | 21 | BUSY |
| 12 | 23 | -PAPER_OUT |
| 13 | 25 | -SELECTED |
| 14 | 2 | -AUTO_LF (unused by MIRE) |
| 15 | 4 | -ERROR |
| 16 | 6 | -INIT |
| 17 | 8 | -SELECT_PRINTER (unused by MIRE) |
| 18-25 | 10,12,14,16,18,20,22,24,26 | Ground |
Many modern printers don't automatically eject the final page of a text listing, instead retaining it in case further printing instructions are forthcoming. You might have to press your printer's "cancel" button to eject the page.
The MIREUTIL floppy image has a control program for PCL-based printers (like many OfficeJets). Use PCL/CMD to send PCL commands to the printer. Use the script file PCLRST/JCL (via "DO PCLRST") before printing to set up the proper line endings for TRS-80 format text files, and after printing to eject any retained final page.