Detailed descriptions
17.2 Bus board
SIMATIC Panel PC 877
17-28 Operating instructions, Release 07/2006, A5E00877780-01
Pin No. Abbreviation Type* Pin No. Abbreviation Type
C1 -SBHE O D1 -MEMCS16 I
C2 LA 23 I/O D2 -IOCS16 I
C3 LA 22 I/O D3 IRQ 10 I
C4 LA 21 I/O D4 IRQ 11 I
C5 LA 20 I/O D5 IRQ 12 I
C6 LA 19 I/O D6 IRQ 13 I
C7 LA 18 I/O D7 IRQ 14 I
C8 LA 17 I/O D8 -DACK0 O
C9 -MEMR I/O D9 DRQ 0 I
C10 -MEMW I/O D10 -DACK5 O
C11 SD 08 I/O D11 DRQ 5 I
C12 SD 09 I/O D12 -DACK6 O
C13 SD 10 I/O D13 DRQ 6 I
C14 SD 11 I/O D14 -DACK7 O
C15 SD 12 I/O D15 DRQ 7 I
C16 SD 13 I/O D16 + 5V VCC
C17 SD 14 I/O D17 -MASTER I
C18 SD 15 I/O D18 0 V GND
Under normal conditions, the signals -SBHE, LA17 - LA23, -MEMR and MEMW are operated
as outputs (sending from the CPU). Only CPU modules which are suitable for use as a
master CPU for system bus access send and receive these signals. A minus sign “-” in front
of the signal name shows that the signal is LOW active.