Poll Encoder Interrupts

Polls the encoder interrupts of the Q8 data acquisition system.

Library

qctools

Description

The Poll Encoder Interrupts block for the Q8 series of I/O cards provides a mechanism for polling the interrupts associated with the encoders. It reads the Interrupt Status Register of the Q8 card. An output goes high when the associated interrupt occurs. The block has an option for resetting the interrupt flags after an interrupt occurs. The block polls the Interrupt Status Register each sampling instant. The Poll Interrupts series of blocks may be used in Windows regardless of the status of the Q8 Windows driver.

Block Outputs

FLG1

The output goes high when FLG1 of the selected encoder channel goes high. The output is edge-triggered. The value of FLG1 may be configured using an Encoder Input block or the Configure Encoder I/O block.

FLG2

The output goes high when FLG2 of the selected encoder channel goes high. The output is edge-triggered. The value of FLG2 may be configured using an Encoder Input block or the Configure Encoder I/O block.

Parameters and Dialog Box

Board Number

The board number of the I/O card. If there is only one Q8 board in your system, then the board number should be zero. The second Q8 board in your system is board number 1, etc.

Channel

The encoder channel whose flags are being polled. The channel number may range from 0 to 7, since there are 8 encoder channels on the Q8 I/O boards.

Sample Time

A sample time must be specified for all discrete blocks. The default value extracts the sample time from the RTW Options dialog, under Solver/Fixed step size. A numeric value rather than 'auto' should be specified in this dialog field for this default to make sense.

Clear Flag After Polling

When this option is checked, the block clears the polled bits of the Interrupt Status Register after reading them. This option allows the flags to be repeatedly polled. The outputs will remain high for one sampling instant when this option is checked. Otherwise, an output stays high once it has gone high.