Difference between revisions of "Project:HM55B"

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  READ BIT: 0
 
  READ BIT: 0
  
Note that you need to delay with &&, because &:50000 doesn't seem to work, but the BusPirate parser obviously creates enough of a delay.  This means that we don't know how fast it can be clocked, because each ! will be > 50ms apart.
+
Note that &:50000 isn't enough of a delay, but && works, presumably because BusPirate parser adds a huge delay.  This means that we don't know how fast this module can be clocked, because each ! will be > 50ms apart.
  
 
Sample values:
 
Sample values:

Revision as of 23:59, 2 September 2010

Module

$20-25 compass module for embedded systems. SMD will be cheaper.

Datasheet


Testing with the BusPirate

BusPirate settings:

  • M (mode)
  • 8 (3-wire raw)
  • 4 (400KHz)
  • 2 (3.3V high)
  • W (turn on 5V output)

Reset:

\[/_\/_\/_\/_\&:10]
RAW3WIRE>\[/_\/_\/_\/_\&:10]
CLOCK, 0
CS ENABLED
CLOCK, 1
DATA OUTPUT, 0
CLOCK, 0
CLOCK, 1
DATA OUTPUT, 0
CLOCK, 0
CLOCK, 1
DATA OUTPUT, 0
CLOCK, 0
CLOCK, 1
DATA OUTPUT, 0
CLOCK, 0
DELAY 0b00001010uS
CS DISABLED


Take sample (1100 is the response for success, 00xx is for incomplete, xx11 is error, see p9 of datasheet)

\[/-\/_\/_\/_\&&]&:10[&:10/-\/-\/_\/_\!!!!&!!!!!!!!!!!&!!!!!!!!!!!]
READ BIT: 1
READ BIT: 1
READ BIT: 0
READ BIT: 0
DELAY 0b00000001uS
READ BIT: 0
READ BIT: 0
READ BIT: 0
READ BIT: 0
READ BIT: 0
READ BIT: 0
READ BIT: 1
READ BIT: 0
READ BIT: 0
READ BIT: 0
READ BIT: 0
DELAY 0b00000001uS
READ BIT: 1
READ BIT: 1
READ BIT: 1
READ BIT: 1
READ BIT: 1
READ BIT: 1
READ BIT: 1
READ BIT: 1
READ BIT: 1
READ BIT: 0
READ BIT: 0

Note that &:50000 isn't enough of a delay, but && works, presumably because BusPirate parser adds a huge delay. This means that we don't know how fast this module can be clocked, because each ! will be > 50ms apart.

Sample values:

0,-6

-1,-11

-1,-19