Wil keep trying on and off, but does anyone have any ideas?
The problem with non-standard serial ports is that, rather than using the serial port as intended, the cheapo tech2 uses a couple of the handshake lines and "bit bashes" them in software, using timing loops and other evil to generate the required waveforms with the required timing.
If the machine is directly connected, through a simple driver, to a real UART the calls the code makes to change the state of the handshake lines translate into immediate (or pretty much) transitions of the pins at the serial port. If the driver is actually piping the commands over a USB port, for example, the timing gets totally messed up and it's unlikely to work.
PCMCIA is an unknown quantity in that, in theory, it's a bus so you could implement a serial port by hanging a proper UART off the bus. Who knows what they're actually doing, though? The problem is the timing of the handshake lines are not normally that critical in a real serial port due to large buffers either end, so a bodged port is likely to be lacking in this respect.
Has the interface you have worked with a "real" serial port? That would be my starting point, get it working with a machine with a genuine serial port and then compare the timing of the waveforms you get.
Kevin
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Topic: Tech 2 (Read 6555 times)