IC-MD Datasheet, PDF (14/23 Pages) IC-Haus GmbH – ENCODER RECEIVER/COUNTER WITH SPI AND BiSS

iC-MD RS-422 QUADRATURE
preliminary
ENCODER RECEIVER/COUNTER WITH SPI AND BiSS
TP1, TP2 and AB REGISTERS
Rev A1, Page 14/23
TP1, TP2 Registers
The touch probe registers consist of two 24 bit regis-
ters which are load with a TPI pin event (see table 19)
or writing the instruction bit TP (table 24) via SPI/BiSS.
At every TPI pin or TP instruction event, the register
TP2 is load with the value of TP1 and TP1 is load with
the actual value of counter 0.
For using TP registers, AB counter must be configured
to 24 bit, but if 2x24 bit counters are configured, only
the counter 0 will be latched into TP1/TP2 registers.
The TPI pin events can be configured as falling, rising
or both edges, as shown in table 19.
TPCFG
Addr. 0x01; bit (2:1)
00
Code
Function
00
both edges active
01
rising edge active
10
falling edge active
11
pin TPI disabled
Table 19: TPI Pin Configuration
The following diagram (figure 5) shows the function of
the pin TPI when configured for both rising and falling
edge.
Figure 5: Function of TPI pin when TPCFG=11
AB Register
A 48 bit register (AB) is used to store and shift out the
ABCNT Registers (Counters), and also the "SPI Chan-
nel Data" (SPICH). The register AB is read via BiSS
(sensor data, channel 0) or via SPI (Adr 0x08), and
the bit length is set by the configuration bits CNTCFG
(table 16)
The bit CH0SEL (table 45) selects the data to be load
in the AB register when reading the channel 0 via BiSS
or the address 0x08 via SPI.