LPT5..8 (AREV Specific)
At 29 APR 1998 01:12:18AM Barry Stevens wrote:
Should Arev be able to print to Logical ports LPT5 thru LPT8 or is there something special that needs to be done. LPT1 to LPT4 are ok.
I have expanded the printer environment window to allow more entries, but, like I said if I add LPT5, nothing is printed.
Barry
At 29 APR 1998 07:04AM Steve Smith wrote:
Barry, it probably depends on the port addresses, eg. 278h, 2F8h, 3F8h
etc. and whatever device driver/TSR you have supporting these. Guessing, you could always pdisk to a local file and then copy /b filename.ext lptx from DOS. You might even be able to PDISK lptx and print directly. There is a DOS PC-MAG TSR utility called prn2file.com which would probably let you print to the file lpt1-8. From DOS, you can always ECHO ^L ] lptx to test the physical connection outside of AREV.
Steve
At 29 APR 1998 09:34PM Barry Stevens wrote:
Steve
Barry, it probably depends on the port addresses, eg. 278h, 2F8h, 3F8h
Please explain . What is the problem with the addresses
At 29 APR 1998 11:32PM Steve Smith wrote:
DOS assigns the logical filenames lpt1-3 to physical memory addresses. It also assigns an IRQ to each port to determine hardware priority (usually hardware IRQ 7 for lpt1, although most recent arallel boards allow reassignment of both addresses and IRQs)
In software, something has to relate the port's memory address with the logical device. I would presume that a device driver (*.sys)
would make these logical files lpt5..8 available, written to support the specific hardware settings.
DOS handles lpt1-3. You write to lpt1, like any other file it determines the address and turns that into characters reaching
a low-address memory buffer at say 0000:03f8 After that, the port addresses are not standardised, so something has to relate the logical files lpt5..8. to their physical addresses (set on the card).
I doubt AREV has knowledge of much more than lpt1-3.
Understand I'm no expert in these things - I've seldom seen much more than lpt1-3 in active use. Someone please correct me if I am mistaken or misleading in this instance.
Steve