I'm having a bit of hassle getting an RFID reader to work- Texas S6050. It is very simple; you send it a carefully crafted stream of bytes and it sends a similar stream back. Or goes completely dead. It has a "data" light on the front that flashes when it's communicating with the PC. This light flashes the first time I send something, and then the unit stops doing anything. Since I have a laptop and 6036 card lying around, and I have a demo program for this reader, I think I'm going to end up doing a simple serial analyser and seeing what the differences are between my code and the demo. But that's not going to happen till next week and it will waste quite a bit of time so I thought I'd see if anyone had suggestions.
I'm pretty sure the present problem is in the sending stage; "bytes at serial port" remains zero after the send. The first hurdle was finding the right baud rate; the manual specifies that there are 4 but doesn't say how to select them. So I tried all four and the "Data" light flashes on only one so it's a fair bet I have the right value. The next is in the other port settings. The manual specifies 1 start bit, 8 data bits, 1 stop bit, no parity. The VISA serial stuff in Labview 7, which I've only just started playing with, has properties for stop bits, data bits and parity which I've set, but I can find no option for start bits. Is this a problem? On the offchance, I've tried all three numbers for "stop bits" with no success. The bytestream can contain null characters, so I've found the "Discard NUL" property and switched it off. Since it's three wire communication- ground, rxd and txd, I've set handshaking to none. I've also disabled the termination character. Again on the offchance, I've tried sending an additional null byte at the end but it didn't help. Does anyone have any suggestions? -- Dr. Craig Graham, Software Engineer Advanced Analysis and Integration Limited, UK. http://www.aail.co.uk/
