Reading Module Status; Module Status Words; Table 3-5 Module Status Words; Table 3-6 Bit Definitions For Status Words Wx17 And Wx18 - Siemens SIMATIC TI505 User Manual

3.3

Reading Module Status

Module Status
Words

Table 3-6 Bit Definitions for Status Words WX17 and WX18

Word.Bit
WX17.01 Not used (0)
WX17.02 Not used (0)
WX17.03 Ch1, Counters 2 and 3: count up when bit is set, count down when bit is cleared
WX17.04 Ch1, Counter 1: Quadrature direction; count up when bit is set, count down when bit is cleared*
WX17.05 Ch1, Counter 1: Sign; set after counter is reset or when it overflows; cleared when it underflows
WX17.06 Ch1, Counter 1: Compare Toggle; cleared after a counter reset; toggles when count equals preset
WX17.07 Ch1, Counter 1: Carry Toggle; cleared after a counter reset; toggles when counter overflows
WX17.08 Ch1, Counter 1: Borrow Toggle; cleared after a counter reset; toggles when counter underflows
WX17.09 Not used (0)
WX17.10 Not used (0)
WX17.11 Ch2, Counters 5 and 6: count up when bit is set, count down when bit is cleared
WX17.12 Ch2, Counter 4: Quadrature direction; count up when bit is set, count down when bit is cleared*
WX17.13 Ch2, Counter 4: Sign; set after counter is reset or when it overflows; cleared when it underflows
WX17.14 Ch2, Counter 4: Compare Toggle; cleared after a counter reset; toggles when count equals preset
WX17.15 Ch2, Counter 4: Carry Toggle; cleared after a counter reset; toggles when counter overflows
WX17.16 Ch2, Counter 4: Borrow Toggle; cleared after a counter reset; toggles when counter underflows
WX18.01 Module in Run mode (Run flag)
WX18.02 Update Preset values complete
WX18.03 Error Flag
WX18.04 User output power failure detected, or voltage below limits for proper operation
WX18.05 Interrupt function is enabled
WX18.06 Latched Interrupt is active
WX18.07 Outputs are disabled
WX18.08 Counters 1 & 4 count format: double 16-bit signed integer (0) or 32-bit signed integers (1)
WX18.01 = 1, 18.06 = 0
WX18.09 Output 8 On/Off status
WX18.10 Output 7 On/Off status
WX18.11 Output 6 On/Off status
WX18.12 Output 5 On/Off status
WX18.13 Output 4 On/Off status
WX18.14 Output 3 On/Off status
WX18.15 Output 2 On/Off status
WX18.16 Output 1 On/Off status
*When counter is in non-quadrature mode, this bit is set.
3-6 Understanding Module Operation
The PLC reads the module status bits in word inputs WX17 and WX18. The
on/off status of the eight outputs, count direction, interrupts, module mode,
error conditions, and other indicators are contained in these words, listed in
Table 3-6. (Status word format is shown in Table 3-5.)
Word
WX17 1 2 3
WX18 1 2 3
Interrupt Active Mode (WX18.01 = 1 and WX18.06 = 1)
Output 8 has changed state, causing interrupt request to the PLC
Output 7 has changed state, causing interrupt request to the PLC
Output 6 has changed state, causing interrupt request to the PLC
Output 5 has changed state, causing interrupt request to the PLC
Output 4 has changed state, causing interrupt request to the PLC
Output 3 has changed state, causing interrupt request to the PLC
Output 2 has changed state, causing interrupt request to the PLC
Output 1 has changed state, causing interrupt request to the PLC

Table 3-5 Module Status Words

MSByte
4 5 6 7 8
4 5 6 7 8
Description
High Speed Counter Encoder Module User Manual
LSByte
9 10 11 12 13 14 15 16
9 10 11 12 13 14 15 16