Technical Description
Sealevel Systems
PLC-16.PCI
Page
11
Register Description
Address
Mode D7 D6 D5 D4 D3 D2 D1 D0
Base+0
RD/WR PAD7 PAD6 PAD5 PAD4 PAD3 PAD2 PAD1 PAD0
Base+1
RD
{0}
{0}
{0}
{0}
{0}
{0}
{0}
{0}
Base+2
RD/WR PCD7 PCD6 PCD5 PCD4 PCD3 PCD2 PCD1 PCD0
Base+3
RD
{0}
{0}
{0}
{0}
{0}
{0}
{0}
{0}
Base+4
RD
{0}
{0}
{0}
{0}
{0}
{0}
{0}
{0}
Base+5
RD/WR
IRQEN
IRQST
{0} {0} {0} {0} IRC1
IRC0
Base+6
RD
{0}
{0}
{0}
{0}
{0}
{0}
{0}
{0}
Base+7
RD
{0}
{0}
{0}
{0}
{0}
{0}
{0}
{0}
Note: When selecting the Interrupt Mode, always disable interrupts prior to changing or setting states. This will
help prevent inadvertent or un-expected interrupts from occurring. When using the high and low level interrupts, a
change in state of the input must occur before the interrupt can be cleared. The device providing the input to Base
+0, bit D0 must do this.
PAD0-7
= Port A (Base+0) Input port.
PCD0-7
= Port C (Base+2) Output port.
IRC0-1= Interrupt Mode select (Base+5)
IRC1 IRC0 Interrupt
Type
0 0 Low
Level
0 1 High
Level
1 0 Falling
Edge
1 1 Rising
Edge
IRQEN = enable interrupts (Base+5)
0 = disabled
1 = enabled (disabled after reset or power up).
IRQST = interrupt status (Base+5)
1 = interrupt pending (reading the bit clears interrupt).
