PNI CommBoard User Manual
Page 17
PNI Sensor Corporation
DOC#1018122 r02
PNI CommBoard User Manual
Page 15
Example #1: $0r84nii$1
The breakdown of this command is as follows:
$0
Set SSN line LOW
r
Set the CommBoard to Read Mode
84n Begin Read Mode by first sending 0x84 to the RM3100 module. 0x84 is
the register read address of the MSB of the X-axis cycle counter register.
If the Read command, “r”, is immediately followed by a value, then the
value must be followed with an „n‟ character. This is because a value
immediately following the “r” character is interpreted as the register
address in a Read-Simultaneous-Write operation. The CommBoard will
write the address to the MOSI line while simultaneously reading the
MISO line. The “n” will read the return byte, “00”, on the MISO line.
For the remainder of the Read operation the CommBoard will set the
MOSI line to zero.
ii
Read two 16-bit words from the SPI bus. To do this, the CommBoard will
create 32 total clock pulses to read the data from the SPI bus.
$1
Set SSN line HIGH
The received signal is: “00 00C8 00C8”. This indicates both X and Y-axis
cycle count registers are set to 0x00C8, or 200
d
(default value).
Example #2: $0wn84rii$1
The breakdown of this command is as follows:
$0
Set SSN line LOW
w
Set the CommBoard to Write Mode.
n
This sets the word length to 8-bits. The CommBoard will interpret all
subsequent write data as such until it is changed. In this case, sending a
[NIML] character is optional. If a [NIML] character was not sent, then the
Write command would use the last [NIML] character sent to the
CommBoard, even if the last [NIML] was sent in a prior Read operation.
84
This sends a 0x84 to the RM3100 module. 0x84 is the read register
address of the MSB of the X-axis cycle counter register.
ii
Read two 16-bit words from the SPI bus. To do this, the CommBoard will
create 32 total clock pulses to get the data from the SPI bus.
$1
Set SSN line HIGH