Echelon I/O Model Reference for Smart Transceivers and Neuron Chips - Manual (Page 139)

I/O Model Reference 129
TCCLK_* macros defined in ). This function overrides the
resolution value specified for clock() within the I/O object declaration.
See Appendix A, Timer/Counter Periods and Resolution , on page 187, for a
description of the timer resolution and maximum range for each specification
of the clock() value or each value of the TCCLK_* macros. See the Neuron C
Reference Guide for information about the io_set_clock() function.
io-object-name
A user-specified name for the I/O object, in the ANSI C format for variable
identifiers.
Usage
unsigned long input-value , control-value ;
io_in_request( io-object-name , control-value );
input-value = io_in( io-object-name );
Example
IO_4 input dualslope ded clock(0) ioDualSlope;
mtimer repeating goTime;
unsigned long data;
...
when (reset) {
goTime = 500; // Perform a measurement every 500ms
}
when (timer_expires(goTime)) {
// Start the first integration period (9ms at 10MHz).
io_in_request(ioDualSlope, 45000UL);
}
when (io_update_occurs(ioDualSlope)) {
// The value at input_value is biased by the
// negative value of the control value used.
// Correct this by adding it back now.
data = input_value + 45000UL;
}
Edgelog Input
The edgelog I/O model can record a stream of input pulses that measure the
consecutive low and high periods at the input and store them in user-defined
storage (see Figure 49 on page 130). The values stored represent the units of
clock period between rising and falling input signal edges.
For a Series 3100 device, this I/O model measures a series of both high and low
input signal periods on a single input pin, IO_4, in units of the clock period:
time_on/time_off (ns) = value_stored * 2000 * 2^(clock) / input_clock (MHz)
where clock ranges from 0..7