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ASIC Interface
PROFIBUS Controller SPC 4®-2 LF
C79000-G8976-C157-3
91
7.8
Error Trigger Signal
This signal should be used to trigger an oscilloscope if a transmission error occurs.
It should be activated either by receive or send errors. A receive error means that
the SPC 4-2 receiver detected an error in the bit stream. A send error means that
the frame sent by the SPC 4-2 differs from the simultaneously received frame. The
error trigger signal is led out via the XHOLDTOKEN pin, is zero-active, and in all
cases has a minimum width of 1/4 bit time (except in operation with pulse
modulation where the minimum width is the pulse width).
Receive errors:
Both in the PA and in the DP mode, the error bit of each character is used (in the
PROFIBUS PA or FF mode, these are Manchester bit errors, in the PROFIBUS DP
mode, start bit, parity, stop bit errors). This bit is updated after each character is
received. In the PA mode, the CRC error signal, that can only be active once at the
end of a frame while a frame is being received, is also checked. In the DP mode,
the same applies to the checksum error signal. A FIFO overflow also counts as a
receive error.
Send errors:
The send pin of the SPC 4-2 is bi-directional; in other words, the SPC 4-2 can
check which level is supplied to its TXD_TXS send pin when sending. Instead of
this level, it can also check using the value supplied by the RXD_RXS input pin.
This means that there are four different modes for the SPC 4-2 XHOLDTOKEN pin:
0. Normal operation as with the SPC 4-1
1. Error trigger signal for reception
2. Error trigger signal for sending (comparison with the level at TXD_TXS)
3. Error trigger signal for sending (comparison with the normal or inverted level at
RXD_RXS; can be set with the RXD_RXS level bit of mode register 3); in this
case, the external propagation time from the TXD_TXS send pin to the local
RXD_RXS receive pin must be taken into account; depending on the mode,
there is an upper limit for this value:
4.
PROFIBUS
DP: 1
bit
time
PROFIBUS PA/FF mode without pulse modulation:
0.5 bit times
PROFIBUS PA/FF mode with pulse modulation:
1 period of
QCLK_IN
The active mode is set with the XHOLDTOKEN mode bits of mode register 3.
Содержание SIMATIC NET SPC 4-2 LF
Страница 9: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 9 Introduction 1 ...
Страница 11: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 11 Functional Overview 2 ...
Страница 14: ...PROFIBUS Controller SPC 4 2 LF 14 C79000 G8976 C157 3 ...
Страница 15: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 15 Pin Assignment 3 ...
Страница 18: ...PROFIBUS Controller SPC 4 2 LF 18 C79000 G8976 C157 3 ...
Страница 19: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 19 Memory Assignment 4 ...
Страница 32: ...PROFIBUS Controller SPC 4 2 LF 32 C79000 G8976 C157 3 ...
Страница 33: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 33 FLC Interface 5 ...
Страница 50: ...PROFIBUS Controller SPC 4 2 LF 50 C79000 G8976 C157 3 ...
Страница 51: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 51 DP Interface 6 ...
Страница 63: ...ASIC Interface PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 63 ASIC Interface 7 ...
Страница 107: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 107 Asynchronous Interface 8 ...
Страница 114: ...PROFIBUS Controller SPC 4 2 LF 114 C79000 G8976 C157 3 ...
Страница 115: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 115 Synchronous Interface 9 ...
Страница 125: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 125 Clock Pulses 10 ...
Страница 128: ...PROFIBUS Controller SPC 4 2 LF 128 C79000 G8976 C157 3 ...
Страница 129: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 129 Processor Interface 11 ...
Страница 152: ...PROFIBUS Controller SPC 4 2 LF 152 C79000 G8976 C157 3 ...
Страница 153: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 153 Technical Specifications 12 ...
Страница 159: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 159 Package 13 ...
Страница 165: ...Package PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 165 Figure 13 4 Tray Spezification ...
Страница 166: ...PROFIBUS Controller SPC 4 2 LF 166 C79000 G8976 C157 3 ...
Страница 168: ...PROFIBUS Controller SPC 4 2 LF 168 C79000 G8976 C157 3 ...
Страница 169: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 169 Addresses 15 ...
Страница 172: ...PROFIBUS Controller SPC 4 2 LF 172 C79000 G8976 C157 3 ...
Страница 173: ...PROFIBUS Controller SPC 4 2 LF C79000 G8976 C157 3 173 Appendix 16 ...
Страница 178: ...PROFIBUS Controller SPC 4 2 LF 178 C79000 G8976 C157 3 ...