Question about COM port wiring on custom board for a BS2p
ddbcretin
Posts: 6
Hello again. 
I've wired a small protoboard for a BS2p that I'm using to control some heater and time events. The variables for the events are set using a VB GUI. With your help I got the comm issues worked out between VB and the Stamp. Thanks again for that. Everything worked well on the benchtop board when I used your Demo Board. However, when I tried the board I wired I have issues communicating between the PC and the Stamp. Size constraints prevent me from using a stock board in the delivered unit.
I'm using pin 16 to communicate with the Stamp. I wired the COM port according to the book directions (and I've checked it repeatedly). I can recognize the Stamp with your editor and can program it. The program runs normally, except that I can't communicate with a PC. Close examination of the Demo Board shows me that C2 anc possibly C3 play a roll in the COM port. There is a connection to the ATN pin. I suspect this is my problem. As the board appears to be multi-layer I can't follow all the traces. Can you point me to a more detailed wiring diagram of the Demo Board's COM port? Also, can you tell me the values of C2 and C3 (and any other required components). Thanks.
I've wired a small protoboard for a BS2p that I'm using to control some heater and time events. The variables for the events are set using a VB GUI. With your help I got the comm issues worked out between VB and the Stamp. Thanks again for that. Everything worked well on the benchtop board when I used your Demo Board. However, when I tried the board I wired I have issues communicating between the PC and the Stamp. Size constraints prevent me from using a stock board in the delivered unit.
I'm using pin 16 to communicate with the Stamp. I wired the COM port according to the book directions (and I've checked it repeatedly). I can recognize the Stamp with your editor and can program it. The program runs normally, except that I can't communicate with a PC. Close examination of the Demo Board shows me that C2 anc possibly C3 play a roll in the COM port. There is a connection to the ATN pin. I suspect this is my problem. As the board appears to be multi-layer I can't follow all the traces. Can you point me to a more detailed wiring diagram of the Demo Board's COM port? Also, can you tell me the values of C2 and C3 (and any other required components). Thanks.
Comments
·· The schematic for the connections to the communications port is listed on page 26 of the current BASIC Stamp Manual, a free download from our website if you don't have a copy.· It shows the values of the 2 capacitors.
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Chris Savage
Parallax Tech Support
csavage@parallax.com
Thanks again.