Manual

© Sealevel Systems, Inc.
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PLC-16.PCI User Manual
Input Port Pin Assignments (HD44 Female)
The inputs are not polarized and can be wired in either direction.
Port A Bit P1
D0 9,10
D1 11,12
D2 13,14
D3 23,24
D4 25,26
D5 27,28
D6 29,30
D7 40,41
Output Ports (Form C Relays)
The PLC-16.PCI provides 8 Form C (SPDT) Electro-mechanical relays. These
relays have three connections: Normally Open (NO), Normally Closed (NC) and a
Common. The relays are all de-energized at power-on. Data to the relays is latched
by a write to the base+2 address. On/off status of the relays can be read back by a
read at the base+2 address.
Output Port Pin Assignments (HD44 Female)
Port C Bit Normally Closed Common Normally Open
D0 (K1) 1 16 31
D1 (K2) 2 17 32
D2 (K3) 3 18 33
D3 (K4) 4 34 35
D4 (K5) 5 19 36
D5 (K6) 6 20 37
D6 (K7) 7 21 38
D7 (K8) 8 22 39
Direct Hardware Control
In systems where the user’s program has direct access to the hardware (i.e. DOS) the
table below gives the mapping and functions that the PLC-16.PCI provides.
Function Available Port Address Hex Port Type
RD A Base+0 Input Port (Opto Input)
B Base+1 Not Assigned
RD/WR C Base+2 Output Port (Reed Relays)
D Base+3 Not Assigned
RD = Read, RD/WR = Read or Write
Reading the Inputs
The inputs are active Low. If no voltage is applied across one of the differential
inputs it returns a binary one (1) on that bit. If an AC or DC voltage is applied it
returns a binary zero (0) on that bit.