SYSTEM@DBNPIB5.BITNET.UUCP (03/14/87)
Here is a comment to W. Reichenbaechers question about spooling TEX-output and normal Printer-output. The farmost best wold be to write an Printsymbiont, that accepts a switch like /TEX and than interprets the .DVI - file. But that is a lot of work and has some principal diffiences. The second way is to stop the print-qwueue, give the printer to the user or a specialized progam, do the Tex-output and come back again to the Print-queue. This gives you always trouble. First its not handy. Second, the printer is usually for reasons of speed connected to the DMF parallel port. Then you let one of your students write the print-program. He thinks its an DMA-device, which not give it the whole page in one bunch of about 1 Mb. Thats the moment, when the system crashes with UBMAPEXCED due to the fact, that at the lcdriver doesn't properly check the upper bound of 64bytes. In fact, though nowhere mentionend in the documentation, LCDRIVER does only use the last 16 bit of the wanted bufferlength. The system crashes if you give a qio with more than 32 Kbytes. This has been SPRed, a solution has been given to us by our local DEC-office but DEC-Engeneering until now now doesn't accept this as an error. So this was a warning of using big QIOs to an LCDRIVER which is "commonly" available. The third way is just to print the TEX-outputfiles just using the /PASSALL option. The only sad aspect of this is that there is no accounting information on hown many pages were acctually written. We use this option for all sort of Pixel-Images that we print. At the end a private question: To speed up output to the printer - a DMF has a maximum throughput of about 30 Kbytes/second - we use a modifyed DR11W which gives us about 200 kbytes/Sec on a 11/725. The problem here is to keep the XADRIVER happy and have all output with an even number of bytes. So we use our own printsymbiont. Now the Question: is there DMA-Device on the market that works on byte-count and not on words as the DR11W and is as fast as the DR11W? The best would be a DECSERVER-like device which can be put onto ETHERNET? Peter Kobe Physikalisches Institut der Universitaet Bonn EARN/Bitnet SYSTEM@DBNPIB5