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For Bean or anyone that uses PROPBASIC...

dennodenno Posts: 223
edited 2020-08-29 21:17 in Propeller 1
Having trouble with I2C in PROPBASIC with the HMC6352 compass from Sparkfun. In PBASIC I do this, and it works. 
HMC6352: (Not all GOSUB's are displayed.
'first read
  GOSUB I2C_Start                            ' Start communications on the I2C buss
  I2C_DATA = HMC6352_WRITE
  GOSUB I2C_Write                            ' Address the HMC6352 in write mode
  I2C_DATA = GET_HEADING_command
  GOSUB I2C_Write                            ' Send the get rawHeading command
  PAUSE 10
  GOSUB I2C_Stop                             ' End communications on the I2C buss
  PAUSE 10
  GOSUB I2C_Start                            ' Start communications on the I2C buss
  I2C_DATA = HMC6352_READ
  GOSUB I2C_Write                            ' Address the HMC6352 in read mode
  PAUSE 10                                   ' Give the HMC6352 time to calculate the rawHeading
  GOSUB I2C_Read
  rawHeading.HIGHBYTE = I2C_DATA                ' Read in the high byte
  GOSUB I2C_ACK
  GOSUB I2C_Read
  rawHeading.LOWBYTE = I2C_DATA                 ' Read in the low byte
  GOSUB I2C_NACK
  GOSUB I2C_Stop                             ' End communications on the I2C buss
  PAUSE 10
  rawHeading = rawHeading / 10               'whole degrees
'      DEBUG DEC4 ? rawheading
  RETURN

The problem I'm having in PROPBASIC is joining the HIGHBYTE and LOWBYTE, as seen in the code below: Adding "heading1" and "heading2" does not work.
SUB compass_get_heading
  I2CSPEED 1
  I2CSTART HMC6352_data,HMC6352_clk
  I2CWRITE HMC6352_data, HMC6352_clk, HMC6352_WRITE
  PAUSE 10
  I2CWRITE HMC6352_data, HMC6352_clk, GET_HEADING
  PAUSE 10
  I2CSTOP HMC6352_data, HMC6352_clk
  PAUSE 10
  I2CSTART HMC6352_data,HMC6352_clk
  I2CWRITE HMC6352_data, HMC6352_clk, HMC6352_READ
  PAUSE 10
  I2CREAD HMC6352_data, HMC6352_clk, heading_HIGH_byte, 0
  PAUSE 10                                   ' Give the HMC6352 time to calculate the rawHeading
  I2CREAD HMC6352_data, HMC6352_clk, heading_LOW_byte, 1
  PAUSE 10
  I2CSTOP HMC6352_data, HMC6352_clk
  PAUSE 10
  heading1 = heading_LOW_byte 
  heading2 = heading_HIGH_byte 
ENDSUB

Any words of wisdom. I am using the FLIP module..thanks to all

Comments

  • BeanBean Posts: 8,129
    You would need to multiply the high byte by 256, then add it to the low byte.

    heading2 = heading2 * 256
    heading1 = heading1 + heading2

    heading1 should now contain the correct value.

    Bean
  • dennodenno Posts: 223
    edited 2020-08-31 13:41
    Bean, thank you for your response. Wow, something so simple. I have spent hours trying to sort that little problem out. Thank you for your help. I do enjoy working with PROPBASIC. I guess because, I have been writing PBASIC for decades, yes decades, and I just find PROPBASIC to sort of follow in line with PBASIC.

    What does the I2CSPEED do exactly. Do I really need the "PAUSE 10's" in the SUB routine?
    TASK HMC6352compass LMM 'RUNNING IN COG 2

HMC6352_data   PIN 0
HMC6352_clk    PIN 1
heading             VAR   LONG
heading_HIGH_byte   VAR   LONG
heading_LOW_byte    VAR   LONG
heading1            VAR   LONG
heading2            VAR   LONG
heading3            VAR   LONG
valueSTR_3          HUB   string (3)
compass_get_heading   SUB

'---------[Main Routine]---------------
'================================HMC6352 COMPASS ROUTINE=====================================
 DO
   GOSUB compass_get_heading
    SEROUT 30, baud2, 13
    SEROUT 30, baud2, 10
    SEROUT 30, baud2, "heading "
    SEROUT 30, baud2, valueSTR_3
    PAUSE 50
 LOOP'

SUB compass_get_heading
  I2CSPEED .5
  I2CSTART HMC6352_data,HMC6352_clk
  I2CWRITE HMC6352_data, HMC6352_clk, HMC6352_WRITE
  PAUSE 10
  I2CWRITE HMC6352_data, HMC6352_clk, GET_HEADING
  PAUSE 10
  I2CSTOP HMC6352_data, HMC6352_clk
  PAUSE 10
  I2CSTART HMC6352_data,HMC6352_clk
  I2CWRITE HMC6352_data, HMC6352_clk, HMC6352_READ
  PAUSE 10
  I2CREAD HMC6352_data, HMC6352_clk, heading_HIGH_byte, 0
  PAUSE 10                                   ' Give the HMC6352 time to calculate the rawHeading
  I2CREAD HMC6352_data, HMC6352_clk, heading_LOW_byte, 1
  PAUSE 10
  I2CSTOP HMC6352_data, HMC6352_clk
  PAUSE 10
  heading1 = heading_LOW_byte 
  heading2 = heading_HIGH_byte 
  heading2 = heading2 * 256
  heading3 = heading1 + heading2
  heading3 = heading3 / 10  ''''to get whole degrees..
  valueSTR_3 = STR heading3,4,5
  WRLONG heading3_location, heading3
ENDSUB

ENDTASK ''''''HMC6352
  • dennodenno Posts: 223
    BTW...the HMC6352 is a great compass module, but they (Sparkfun) doesn't offer it anymore. I can hold 1 degree accuracy, if it is on a level plane. I use it to hold an azmuth angle for my directv dish on my boat while it swings at anchor.

    Anyone got a HMC6352 for sale....?
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