B-61813E/03 CONNECTIONS 8. HIGH SPEED COUNTER MODULE
8.3 PMC INTERFACE
8.3.1 Mode A
(1) PMC I/O area
In mode A, four input bytes and four output bytes are used as the
I/O area. The bytes in the I/O area have the following names. The
input and output directions arespecified on the basis of the PMC.
The operation mode is set to mode A at power-on.
1) Output data (sent from PMC to high speed counter module)
0 CTRL (control)
+1 DTOH (higher 8-bit data)
+2 DTOM (middle 8-bit data)
+3 DTOL (lower 8-bit data)
2) Input data (entered from high speed counter module to PMC)
0 CNTS (counter H and status)
+1 CNTM (middle 8 bits of counter)
+2 CNTL (lower 8 bits of counter)
+3 STTS (status)
(2) PMC outputs (outputs from PMC)
The PMC outputs are separated into control output CTRL and
data outputs DTOH, DTOM, and DTOL. As with normal DOs,
the control outputs of bit 3 to bit 7 are controlled independently.
The cotrol outputs of bit0 to bit2 constitute the SELECT
indicating the target data specified by DTOH, DTOM, and DTOL.
1) Control output
MHR MS CE PRS SELECT
PRS : Preset
CE : Count enable
MS : Marker synchronization
MHR : Marker hold reset