Sensoray 2410 API - Manual (Page 21)

Sensoray 24xx Programming Guide
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Model 2410 Digital I/O Module
6.2.6 s2410_WritePwm()
Function: Program the PWM ratio for one DIO channel.
Prototype: BOOL s2410_WritePwm( SESSION sess, u32 *err, u8 chan, u16 ontime, u16 offtime );
Returns: True if the operation was successful, otherwise False is returned and err will contain the associated error code.
Notes: This function applies to channels operating in PWM mode; it has no affect on channels operating in Standard mode.
The
ontime and offtime arguments specify the amount of time that the DIO is to be in the active and inactive
states, respectively. If ontime is zero and offtime is non-zero then the DIO output will always be inactive.
Similarly, if offtime is zero and ontime is non-zero then the output will always be active. The output state is
indeterminate if both ontime and offtime are set to zero.
The designated DIO channel will switch to the active state and remain active until ontime has elapsed, then it will
switch to the inactive state and remain in that state until offtime has elapsed. This sequence will repeat with the
same duty cycle and frequency until one of these events occurs:
• The ontime and/or offtime is changed by calling s2410_WritePwm() .
• The channel’s operating mode is switched from PWM to Standard. The operating mode can be switched under
software control by calling s2410_SetDoutMode() or s24xx_ResetIo() , and it may also be automatically
switched in response to a module hardware reset.
Example: // Configure DIO channel 5 for PWM mode: on for 20 ms, off for 30 ms.
u32 err = ERR_NONE;
s2410_SetDoutMode( sess, &err, 5, DOUT2410_MODE_PWM );
s2410_SetWritePwm( sess, &err, 5, 20, 30 );
if ( err != ERR_NONE )
printf( "Error: %s\n", s24xx_ErrorText(err) );
6.3 Utility Functions
6.3.1 s2410_SetLedBrightness()
Function: Set the brightness level for all DIO status LEDs.
Prototype: BOOL s2410_SetLedBrightness( SESSION sess, u32 *err, uint intensity );
Returns: True if the operation was successful, otherwise False is returned and err will contain the associated error code.
Notes: This can be used to set LED brightness to a comfortable level or to decrease power consumption. DIO status LEDs
can be completely disabled by setting
intensity to 0. Upon boot-up, the LED intensity defaults to 16 (maximum
intensity).
Argument Description
sess Session handle obtained from s24xx_SessionOpen() .
err Pointer to error code. See Section 4.3.1 for details.
chan Channel number in the range 0 to 47.
ontime PWM on time in milliseconds. Range: 0 to 65535.
offtime PWM off time in milliseconds. Range: 0 to 65535.
Argument Description
sess Session handle obtained from s24xx_SessionOpen() .
err Pointer to error code. See Section 4.3.1 for details.
intensity Brightness level: 0 (always off) to 16 (maximum intensity).