Changing Datalogger 27937 Baud Rate

Li Yue

I am trying to change the communication baud rate between BS2 and Datalogger #27937. It doesn’t seem to work. This is the code I am using to change the baud rate of the Datalogger from its default (9600) to 19200 :

Baud CON 84 ' Serial Baud Rate 9600 bps (BS2)
SEROUT TX\CTS, Baud, [$14, $20, $9C, $80, $00, CR]

I would like to know what I am doing is wrong. If any one has any idea, please let me know. Thanks,


Li

Publison

Welcome to the forums!

Your other post was deleted as double posts are not allowed:

http://forums.parallax.com/showthread.php/134682-Forum-Guidelines

Tracy Allen

Are you confident with the connections, and have it working okay at 9600 baud? Seeing the ">" prompt?


Maybe try the ascii mode:
SEROUT TX\CTS, $54, ["SBD $$9C8000", CR]

In general, the Stamp has trouble receiving at higher baud rates due to its unbuffered serial port. Flow control does help with the #27927 datalogger. Nevertheless, the actual throughput will not improve by much, because the Stamp takes time between bytes to process data. You'll never get more than 4800 baud in actual throughput.

xanatos

Digging in my way-back machine, I found this code - this is what I was using to set my datalogger to 4800, before I used a firmware updater to make it power up at the defaults I specified. Don't know if this helps, but here it is:

'***********[INITIALISE LOGGER & DETECT MEMORY STICK]*********
LOW DLTX
DEBUG HOME," Remove Memory and Press 1 ",CR
DO WHILE idx=0
GP_WORD=GP_WORD+1
DEBUGIN DEC1 idx
LOOP
DEBUG CLS
SEROUT DLTX, 240, ["IPA", CR]
PAUSE 200
SEROUT DLTX, 240, ["SCS", CR]
PAUSE 200
SEROUT DLTX, 240, [$14,$20,$71,$02,$00,$0D]  'SET BAUD TO 4800
SERIN DLRX, 500,[WAIT(">")]
DEBUG "Initialized ",CR
PAUSE 200