bing@galbp.LBP.HARRIS.COM (Bing Bang) (09/03/87)
In article <488@ast.cs.vu.nl> ast@cs.vu.nl () writes: >As to kermit, that sounds nice. One thing that is needed is an RS232 >driver. There have been two posted so far (Andy Valencia and Bing Bang), >but both are very large and said to be not fully debugged. I think there >is still a need for a minimal RS232 driver that just drives the serial >port as an I/O device, without also requiring a large number of changes >elsewhere in the system to support multiple users. Hopefully this could >be done in a new file rs232.c, with a few changes to tty.c and not too >many elsewhere. If anyone wants to do this, it would be much appreciated. >Maybe one of the two drivers already posted could be used as a base. > >Andy Tanenbaum (ast@cs.vu.nl) I am still debugging mine. I have hound several inherant problems with implemen- ing any kind of rs232 drivers for minix. One is that minix spends too much time in the video routines with interrupts off. This causes characters to be dropped if they are sent in a burst to minix, as kermit transfers require. The second problem is as minix is now, all writes to the tty devices are not suspended, so that the writes to the rs232 tty will not return untill every byte makes it out of the system. This simple approach is ok for the video console, but not for a rs232 running at 1200 baud. I have tried to address the problems, and like I said I am still debugging mine as my free time allow. I will repost the stuff once i get it all working. In the meantime I would like to hear from some people who might have tried using my driver as it was posted. Any bug report would be nice. I have not recieved a single response yet. -- Bing H. Bang +-------------------+ Harris/Lanier |MSDOS: just say no.| Atlanta GA +-------------------+