thssdwv@iitmax.IIT.EDU (David William Vrona) (07/14/90)
I have two Jameco serial port boards. Each can be configured as either COM1 and COM2 or COM3 and COM4. They use sharable interrupts, i.e. COM1 and COM3 share, etc. I have replaced the UARTs with the 16550AN chips. I still cannot get FAS 2.06 work with these boards. Nor can I get the X5 update from Interactive to work either. The problem I have is that COM3 and COM4 are dead, COM1 and COM2 work fine. I have switched the UART's around, and all reset the addresses, etc. I thought I had read something on the net about cheap multiport boards with sharable interrupts not working with X5. What is the story here? Any anyone had success with the Jameco boards and FAS? FAS is what I really want, but would settle for having X5 work with COM3 and COM4. Thanks.
gemini@geminix.mbx.sub.org (Uwe Doering) (07/17/90)
thssdwv@iitmax.IIT.EDU (David William Vrona) writes: >I have two Jameco serial port boards. Each can be configured as either COM1 >and COM2 or COM3 and COM4. They use sharable interrupts, i.e. COM1 and COM3 >share, etc. I have replaced the UARTs with the 16550AN chips. > >I still cannot get FAS 2.06 work with these boards. Nor can I get the X5 >update from Interactive to work either. The problem I have is that COM3 and >COM4 are dead, COM1 and COM2 work fine. I have switched the UART's around, and >all reset the addresses, etc. I would think that you have been misled by the fact that on your serial cards there are DIP switches or jumpers that allow you to set two ports to the same interrupt. This alone doesn't mean that these cards are capable of shared interrupts. As on every other cheap PC serial card you can only use one of those ports at the same time if you set them to the same interrupt. In the DOS environment this isn't much of a problem as DOS isn't multitasking. Under UNIX all ports have to work at the same time (worst case). Shareable interrupts require a special logic on the serial card as the PC or AT i/o bus itself can't handle shared interrupts. One cheap alternative for you would be one of those AST 4-port clones. FAS generally runs on nearly every board that maps its ports to separate i/o addresses. But this requires that you use the proper hardware as FAS can't compensate hardware limitations. I think I will write a few words about this subject in the README file of the next FAS release to prevent people from wasting their time tinkering with serial cards that simply can't work with FAS due to design shortcomings. Uwe -- Uwe Doering | Domain : gemini@geminix.mbx.sub.org Berlin |--------------------------------------------------------------- West Germany | Bangpath : ...!uunet!pyramid!tub!tmpmbx!geminix!gemini