UART baud rate below 9600

[whiz100]

is it possible to set the baud rate to something less than 9600?

[SupportAdmin]

I believe ti is possible but why lower?

[whiz100]

I'm using a BS2 which is having difficulty with 9600, it's missing bytes when reading data. the BS2 will probably have problems at 4800 also according to the manual.

[SupportAdmin]

BS2+uALFAT then why not use USBizi? Take a look at the free ebook on the USBizi board

[whiz100]

looks very nice, bit overkill for what I need.

couldn't see any reference to setting the baud rate below 9600 for the uALFAT.

so do you know what values I need to set the baud rate below 9600?

thanks
P

[srodriguez14]

Whiz did you ever find out how to use a lower baudrate.

[whiz100]

no i didn't - just could get the BS to work using uart. but I did get it working just fine with some bit banging the SPI.

------------- code below here is for bit banging SPI ---------

Code:

' {$STAMP BS2}
' {$PBASIC 2.5}


' setup o/i pins
dataready PIN 15
busy PIN 14
spi_sck PIN 13
spi_miso PIN 12
spi_mosi PIN 11
spi_ssel PIN 10
reset PIN 9

' INSTRUCTIONS
'>O 1R>boot<CR>
'<!00<CR>
' loop
'>R 1^>1<CR>
'<!00<CR>
'<X$00000001<CR>          ------ result is 1 when something was read, note this is the left that was actuall read ---
'<!00<CR>
' end loop when result is ---- start end of file -----
'>R 1^>1<CR>
'<!00<CR>
'<^$00000000<CR>               ----- result is 0 when nothing left to read -----
'<!00<CR>
'end of file result       ----- finish end of file result -----
'>C 1<CR>
'<!00<CR>
'>Z H<CR>
'<!00<CR>


''''''''''' begin main loop ''''''''''''

cmd VAR Byte(10)
counter VAR Byte

GOSUB func_Reset
DO WHILE dataready=1
    GOSUB func_ReadByte
    DEBUG STR inbyte\1
LOOP

DO
  DEBUG "cmd: "
  DEBUGIN  STR cmd  \10 \13
  'DEBUG STR ? cmd
  FOR counter = 0 TO 9
    IF cmd(counter)<>0 THEN
      outbyte=cmd(counter)
      GOSUB func_WriteByte
    ENDIF
  NEXT

  outbyte=13
  GOSUB func_WriteByte
'PAUSE 500
 DO
 DEBUG "."
   LOOP WHILE (dataready=0)
  DO WHILE dataready=1
    GOSUB func_ReadByte
    IF inbyte<>255 THEN
    DEBUG STR inbyte\1
    ENDIF
  LOOP

LOOP WHILE cmd<>"."
DEBUG "Finished",CR
STOP

'''''''''''''' uALFAT subroutines ''''''''''




func_Reset:
' reset to spi interface
HIGH reset                           ' reset pin
HIGH spi_ssel                           '  spi_ssel# (active low ) set high to activate SPI
HIGH spi_sck                           ' spi_sck set high to active SPI
PAUSE 5
LOW reset                            ' toggle reset
PAUSE 5
HIGH reset                           ' bring reset back
PAUSE 5
RETURN


' results from ReadByte function will be stored in this variable
inbyte VAR Byte
outbyte VAR Byte


func_ReadByte:
LOW spi_ssel   ' activate chip select (active low)
'PAUSE 100
DO:  LOOP WHILE (dataready=0)
HIGH spi_mosi    ' force 0xFF to uALFAT
HIGH spi_sck        ' idle high
bits VAR Byte
FOR bits = 0 TO 7
  LOW spi_sck                          ' ok to read data after this line
 'PAUSE 2
 ' read in the response
  inbyte = inbyte<<1
  inbyte = inbyte | spi_miso
  HIGH spi_sck
NEXT
RETURN



func_WriteByte:

LOW spi_ssel
' check the busy line
DO : LOOP WHILE (busy=1)
FOR bits = 0 TO 7

  IF outbyte.BIT7=0 THEN
  LOW spi_mosi
  ELSE
  HIGH spi_mosi
  ENDIF
  outbyte =outbyte<< 1
  LOW spi_sck
  PAUSE 2
  HIGH spi_sck
NEXT
RETURN