Just thinking that it should be possible to use blitzbasicII to make a small program that does what you want. Not sure if there are a library made for controlling the paralell port.
It's also possible to to access the parallel and joystick ports directly via Arexx. Barry Walker has written some good examples
here plus other hardware projects which might be of interest
here and on Aminet.
Of course it's just as simple to do in C or any other language, port access is essentially reading or writing to a few CIA registers. Set the data pin directions by writing the appropriate 8-bit value to 0xBFE301 and read/write data pin states by reading/writing to 0xBFE101
An analogue temperature sensor (e.g. LM35) with appropriate DC amplification/scaling could be read via the paddle port 7-bit ADC. Or you could use 1-wire temperature sensors such as Dallas 1822 for better resolution. You'd need to implement the Dallas bidirectional serial protocol out of one of the parallel port pins, which would be achievable.
Digital I/O can easily be expanded using shift registers or by multiplexing octal latches. Hundreds of I/O lines are possible providing you don't need to poll them very quickly.
