ZWorld Exp-A/D12, User Manual

Page: 67 / 111

Exp-A/D12 Software Reference s 67
Exp-A/D12 Software
The Exp-A/D12 expansion board can only be used with a BL1200,
BL1600, PK2100, or PK2200 controller with the PLCBus functions in
DRIVERS.LIB
and functions specific to the Exp-A/D12 in
PLC_EXP.LIB
.
Software drivers are not available for the remaining controllers.
The Signal Table
To use the functions in
PLC_EXP.LIB
, create a “signal table” by declaring
an array as shown here.
struct signal_rec adtab[ size ];
The array must be named
adtab
and it must be global. The constant
size
is the number of signals in the table. Plug in the size that the application
needs.
Constants and Data Types
The function library
PLC_EXP.LIB
defines these constants.
#define BREG 0x0200 //add to address for S3B
#define BIPOLAR 0
#define UNIPOLAR 1
The structure
signal_rec
for defining signal tables is also declared in
PLC_EXP.LIB
.
struct{
int address // 12-bit PLCBus address
byte zero_offset // A/D output value at 0v
byte input_ch // Input channel to select
byte mode // conversion mode: 1 of 18
byte comp // 0=no comp. 1=do compensate.
float cal_coef // Calibration coeff. for
// channel
} signal_rec;