PNI SENtral - Manual (Page 46)

PNI Sensor Corporation Doc #1018049 R03
SENtral Technical Data Sheet Page 45
transaction. AFTER the first parameter is written, the ParamTransfer bit in the
AlgorithmControl register must be set to ‘1’. Sentral acknowledges receipt of a parameter
value by setting ParamAcknowledge equal to ParamRequest, and the host should check the
ParamAcknowledge register after writing the first parameter.
Once SENtral acknowledges successfully uploading the first parameter, the host can begin
writing the remaining parameters in a loop. Reading the ParamAcknowledge register is
optional for subsequent parameters. The host terminates the load procedure by setting the
ParamRequest register to 0x00 and the AlgorithmControl register’s ParamTransfer bit to ‘0’.
Parameter Retrieve
The Parameter Retrieve flowchart is given in Figure A3-2.
Figure A3-2: Parameter Retrieve Process
The process is initiated by the host writing to the ParamRequest register the desired (non-
zero) parameter number. The MSB of ParamRequest register should be ‘0’ to indicate a
Retrieve procedure. After writing to the ParamRequest register, the ParamTransfer bit in
the AlgorithmControl register must be set to ‘1’. Next, the host should perform repetitive
reads of the ParamAcknowledge register until it contains the requested parameter number.