Post by thread:[OT]: PALM Programming Question

All, Does anybody know how to generate a "break" signal on the serial port on a PALM IIIc PDA using NS BASIC? Or any language for that matter. I need to generate a break signal on the serial port for about 200ms to allow some processing to happen before I transmit the output data. If anyone knows of a way to do this, please let me know. I'm asking for a way to do this with the PALM H/W only. I can always add something to the serial port to do this, but I would rather use just the H/W that is already there. Thanks all, Regards, Jim

All, I have searched the web, and have contacted several people and groups (NS Basic, and Access Co. [PALM OS]) regarding an API function call in PALM OS. I want to call a serial Break function in the Serial Manager from NS Basic using the API function call command. However, I don't know what the Trap number is for that function, and it seems nobody else does either. Or if they do, they aren't telling. So, my question is, does anyone here know what the Trap number is for the Break function in Serial Manager in PALM OS? Or, alternatively, does anyone have any ideas as to how this can be accomplished within NS Basic? I would appreciate a response either way so I know for sure this request got through. If this is tagged wrong, I apologize. Just let me know for future reference. Thanks and Regards, Jim

On Jul 28, 2008, at 1:37 PM, PAUL James wrote: > Or any language for that matter. I need to generate a break signal on > the serial port for about 200ms One way to generate a BREAK signal on most serial ports is to set the bit rate very low and send a null. A null at 110bps looks pretty much like a 100ms BREAK to a receiver expecting 9600bps... > to allow some processing to happen before I transmit the output data. Um. That isn't one of the traditional reasons for BREAK. Are you trying to use the serial transmission of BREAK to insert pauses in your datastream? Sounds ... weird. APIs that allow accurate timing of a sent (or received) break are getting very rare, you're lucky if you can send any BREAK condition at all (as you are discovering!) There is also "padding", which is traditionally all zero or all ones characters that are hopefully discarded in the driver of the receiver (and therefore consume little resources), but that's also become rare as the overhead of processing serial interrupts gets large compared to the overall overhead of the serial driver... BillW