sato@rinfo.sumiden.co.jp ( Kenya SATO @ SEI ) (08/08/90)
When I try to connect a serial I/O card called Digiboard with a modem
TELEBIT T2000 using the tip command, the following error message is
displayed on the console.
c8[0] line 0: unexpected receive interrupt
It is possible to send data through modem but nothing is echoed back
from the modem to terminal.
I'm using MIPS M120 and RISC/os 4.50, and set jumpers, connectors and
switches on the card by the Serial I/O Board Configuration Manual.
Would anyone tell me what is wrong?
--
Kenya SATO ( sato%rinfo.sumiden.co.jp@uunet.uu.net )
Computer & Information Systems R&D Department
Information & Electronics Technology Laboratories
SUMITOMO ELECTRIC INDUSTRIES, LTD.brudley@mips.COM (Brett Rudley) (08/14/90)
In article <SATO.90Aug8104626@optsei.rinfo.sumiden.co.jp> sato@rinfo.sumiden.co.jp ( Kenya SATO @ SEI ) writes: >When I try to connect a serial I/O card called Digiboard with a modem >TELEBIT T2000 using the tip command, the following error message is >displayed on the console. > >c8[0] line 0: unexpected receive interrupt > >It is possible to send data through modem but nothing is echoed back >from the modem to terminal. > >I'm using MIPS M120 and RISC/os 4.50, and set jumpers, connectors and >switches on the card by the Serial I/O Board Configuration Manual. > >Would anyone tell me what is wrong? > >-- > Kenya SATO ( sato%rinfo.sumiden.co.jp@uunet.uu.net ) > Computer & Information Systems R&D Department > Information & Electronics Technology Laboratories > SUMITOMO ELECTRIC INDUSTRIES, LTD. What is happening is: The device driver for the digiboard usually operates in a polled mode to handle input. When polling like this, the recieve interrupts are disabled. At this point any incoming recieve interrupts will cause the above message. I can think of 3 possibilities: The UARTs on the board could be mixed. The digi supports two models of the National Semi 16X50 uart. Mips does not support the 16450 chip. We do support the 16550 chip. Check your board to make sure you have all 16550s. If you have an 8 port board, recheck your dip switches as these are very easy to accidentily change since there are so many. If you have a 16 port board make sure you have the right PALs. Whether the driver polls or uses interrupt mode is determined by c8_poll_mode in the master.d/c8 configuration file and the presence of the 16450 or 16550 chips. c8_poll_mode is 1 by default and should not be changed (if you want decent performance, that is). brett -- Brett Rudley {ames,decwrl,pyramid,prls}!mips!brudley MIPS Computer Systems - or - 930 Arques Avenue brudley@mips.com Sunnyvale, CA 94086 (408)524-8151