The sillyscope screen fills with Ws with and without external hardware. Whats wrong?
A. Possibly nothing much. This is correct behaviour with no external hardware. With the hardware connected, DSR will be idle high (pulled up by 4k7 resistor) when winsamp is run. IR exposure turns transistor on and pulls DSR low. Because there is no hardware, DSR is already low so the sampler program thinks your photodiode is being exposed to IR (base current turns transistor on and line is pulled down) and starts sampling at once – all WWWWW. If this problem is seen under Windows with hardware attached, possibly some Windows driver / process / application is trying to use the port. There must be NO OTHER DRIVER INTERFERENCE. This relates to my own experience with MS ActiveSync (used to connect my PDA to the PC) – if you have previously run this or normally have it in the background on the same port, it can for example make DSR look high from a status bit point of view even though it is actually externally electrically low. There is no practical way for the dos program to detect and co
