Hi Mike, >>Does BT on the Palm not have the buffer delay bug? No, the BT radio forwards packets to the Palm BT stack as soon as it receives them. The Palm can ACK packets in less than 1 ms, and respond to inbound packets in less than 2ms. In addition, Bluetooth offers higher bandwidth (up to 723 Kbps) than RS-232.
As a "cheap" experiment, it might be worth getting a RS-232 <--> Bluetooth adapter and connecting it to your hardware, then make a small change in your app to use the Bluetooth RFCOMM virtual serial driver. You use the driver like any other serial port; use the SrmOpen or SrmExtOpen calls to open it and the SrmXXXX calls to send/receive data and close the port. Unfortunately, you need to poll the BT serial driver for inbound data (SrmReceiveCheck). If you call the BT library directly you receive a notification of inbound data so you don't need to poll and you get your data immediately. Of course, this is a lot more work, but you have some sample code like BtLibTest and BtPiconet which don't do exactly what you want but provide a good starting point. For the RFCOMM virtual driver, take a look at the BtCommVdrvr.h file in the OS 5 R3 SDK. I have two freeware apps: BtSerial which uses the Srm calls and polls for data and BtSerial Pro which uses the Bluetooth library directly and receives data the instant it is available. I haven't done any work to verify the latency over Bluetooth. I'd be interested in knowing if it meets the theoretical figures mentioned above. With a bit of work I could run some Palm-to-Palm tests. Unfortunately I can't use my BtServer app since it polls for inbound data; I'd have to create "BtServer Pro" which will use the BT lib directly. Regards, Peter http://www.whizoo.com Contractor for hire (PalmSource Certified Developer) Source code available for all apps!! BtSerial Pro - Serial Port Client for the Palm OS BtSerial - Bluetooth Serial Port Client for the Palm OS BtServer - Bluetooth Serial Port Server for the Palm OS Net Sync - Programmatically manipulate network settings RegCode - Add registration code support to your app -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
