Variable Baud Rate
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Hi Will like to ask if anyone has ever try opening a comport with baudrate other than those even in Microsoft APIs? like BaudRate of 141250 etc? I have a device that will work best with this baudrate but could not set the comport baudrate to this value for communication?
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Hi Will like to ask if anyone has ever try opening a comport with baudrate other than those even in Microsoft APIs? like BaudRate of 141250 etc? I have a device that will work best with this baudrate but could not set the comport baudrate to this value for communication?
The Windows API supports any baud rate, but the driver and COM port usually only support a standard set of baud rates (integer factors of 115200; a legacy hardware limitation). If your COM port and driver supports other baud rates, then Windows won't stop you using them.
Ryan
"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"
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Hi Will like to ask if anyone has ever try opening a comport with baudrate other than those even in Microsoft APIs? like BaudRate of 141250 etc? I have a device that will work best with this baudrate but could not set the comport baudrate to this value for communication?
As Ryan says, the standard PC hardware supports a maximum of 115200 bit per second, as well as half that (57600), one quarter (28800), 14400, 9600, 4800, etc. Thus 141250 is not available with standard hardware. I made an interface a few years ago which used two Intersil 6502 UARTS, with different crystal oscillators for each and a little bit of glue logic components - receiving on one UART triggered transmission on the other, so this converted between different baud rates. No buffering or anything, so you had to "go slow". Try posting on the hardware forum - maybe some of the USB-to-serial adapters allow strange rates like you need.