Command byte, Axis select (as1, as0), Period select (ps0, ps1, ps2) – PNI MicroMag User Manual
Page 21: Table 5-1: command byte, Table 5-2: axis select, 2 command byte, 1 axis select (as1, as0), 2 period select (ps0, ps1, ps2)
MicroMag User Manual
– March 2010
Page 21 of 23
5.2 Command Byte
The operation of the MicroMag is controlled by the data received into the SPI port on
the command byte. The command byte syntax is as follows:
Table 5-1: Command Byte
Position
7
6
5
4
3
2
1
0
BIT Name
DHST PS2
PS1
PS0 ODIR MOT AS1
AS0
RESET
0
0
0
0
0
0
0
0
5.2.1 Axis Select (AS1, AS0)
The Axis Select bits establish which sensor is to be measured, as given below
Table 5-2: Axis Select
Axis Measured
AS1
AS0
X axis
0
0
X axis
0
1
Y axis
1
0
Z axis (MicroMag3)
1
1
5.2.2 Period Select (PS0, PS1, PS2)
The Period Select bits establish how many oscillations are to occur for the
measurement. The greater the Period Select, the greater the resolution and the
longer the measurement time. Note that with a Period Select of “4096”, the counter
buffer may overflow.