serial port on DS5000 not responding fast enough to CNTRL/S?

[George Robbins]

In article <900 at usage.csd.unsw.oz.au> mcba at newt.phys.unsw.OZ.AU (Michael C. B. Ashley) writes:
>I have a LaserJet III connected to one of the serial ports on a
>DECstation 5000. My problem is that when I send long files to the
>printer, it loses about 30 bytes every time the LaserJet's input buffer
>fills up. What I think is happening is that the LaserJet is sending a
>control/S to the DS5000 to tell it to stop sending output, and the
>DS5000 doesn't take notice of the control/s until it has sent another 30
>bytes.

Does the LJ have a setting for the the control/s threshold? There's
no particular guarantee that control/s stops transmission after only
one or two characters and you may need to jack up the threshold
appropriately.  On the other hand, the Ultrix driver could be broken...


> 
> Just for the record, we had exactly this same problem when printing from 
> a DS2100 to a Ljet III (with Adobe PS cartridge). Hooking the printer to
> a VAXstation 2000 that we had lying around solved the problem. Both machines 
> run ULTRIX V4.0 - it appears to be hardware based (or device driver). I 
> thought the problem was related to the infamous DS2100/DS3100 -serial port 
> problems and figured that when we get our DS5000 it would be fixed... Your 
> experience seems to indicate that the situation is worse than expected.
> 
> Does any know if this is a known problem with ULTRIX/RISC or the HW ?
> 
> Timo
> 
> -- 
>        ____/ ___   ___/    /		Kivihaantie 8 C 25
>       /           /       /		SF-00310 HELSINKI, Finland
>    ____  /       /       /	Phone:	+358 0 573 161, +358 49 424 012
>   Stream Technologies Inc.	Fax:	+358 0 571 384


-- 
George Robbins - now working for,     uucp:   {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing:   domain: grr at cbmvax.commodore.com
Commodore, Engineering Department     phone:  215-431-9349 (only by moonlite)