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PSD813F2, PSD833F2, PSD834F2, PSD853F2, PSD854F2
External Chip Select
The CPLD also provides three External Chip Se-
lect (ECS0-ECS2) outputs on Port D pins that can
be used to select external devices. Each External
Chip Select (ECS0-ECS2) consists of one product
term that can be configured active High or Low.
The output enable of the pin is controlled by either
the output enable product term or the Direction
Register. (See Figure
31
.)
Figure 31. Port D External Chip Select Signals
P
POLARITY
BIT
PD2 PIN
PT2
ECS2
DIRECTION
REGISTER
POLARITY
BIT
PD1 PIN
PT1
ECS1
ENABLE (.OE)
ENABLE (.OE)
DIRECTION
REGISTER
POLARITY
BIT
PD0 PIN
PT0
ECS0
ENABLE (.OE)
DIRECTION
REGISTER
C
AI02890