Sensoray 2410 API User Manual

Page 19

Sensoray 24xx Programming Guide

Model 2410 Digital I/O Module

6.2.2 s2410_ReadDin()

Function:

Read the debounced physical states of all DIO channels.

Prototype:

BOOL s2410_ReadDin( SESSION sess, u32 *err, u16 *states );

Returns:

True if the operation was successful, otherwise False is returned and

err

will contain the associated error code.

Notes:

Every DIO channel includes a monitoring circuit that enables that channel’s physical state to be read. This function
acquires a snapshot of the physical state of each channel without regard for whether the channel is driven by its
on-board output driver or by an externally generated signal.

Physical states are sampled in parallel (all 48 channels are sampled simultaneously) at one millisecond intervals.
Sample data are passed through a debounce filter which may cause latency or, in the case of rapidly changing
physical states, undetected state changes. Consequently, the values returned in

states[]

may not accurately reflect

the instantaneous physical states of channels that have changed within the debounce interval.

Example:

// Read and display the debounced input states of all DIO channels.

u16 states[3];
u32 err = ERR_NONE;

( !s2410_ReadDin( sess, &err, states ) )

printf( "Error: %s\n", s24xx_ErrorText(err) );

else

printf( "input states: %04x %04x %04x\n", states[2], states[1], states[0] );

6.2.3 s2410_ReadDout()

Function:

Read the programmed output states of all DIO channels.

Prototype:

BOOL s2410_ReadDout( SESSION sess, u32 *err, u16 *states );

Returns:

True if the operation was successful, otherwise False is returned and

err

will contain the associated error code.

Notes:

This function reads the programmed states of all DIO output drivers. Note that these states may differ from those
returned by

s2410_ReadDin()

because channels can be driven by off-board signals as well as on-board drivers.

Also, in the case of channels operating in PWM output mode, the instantaneous driver states are determined by
each channel’s PWM generator.

Example:

// Get all DIO output states.

u16 states[3];
u32 err = ERR_NONE;

Argument

Description

sess

Session handle obtained from

s24xx_SessionOpen()

err

Pointer to error code. See Section 4.3.1 for details.

states

Pointer to an array that will receive the state values. Each bit has the following
meaning:

1 - active state (driven low by on-board driver or off-board signal).
0 - inactive state (pulled high).