I recently purchased a 3com 3cxm556 modem card as I believed it to be compatible with Linux pcmcia/serial drivers. The card is detected and the drivers loaded. It is assigned to device node ttyS0. Fine up to here. The problem comes when I try to read/write to the device. I get nothing. Using the test_modem script in debug_tools, I get a syswrite(): Input/output error. In minicom, nothing, it acts like a winmodem. Same also obviously with KPPP.
Any ideas, I have tried some things from previous posts but with no luck. I had been instructed that this modem was compatible and there are 4/5 online indications that this is the case and with no trouble. Even BSD users seem to like this card. Would the fact that everything on my system seems to like IRQ 11 be an issue?
At minimum you should say what brand and model of laptop this is, and look at your system log for messages from the serial_cs driver.