Z8 Encore!® Motor Control Flash MCUs
Product Specification
42
In each of these three data direction subregisters, bits [7:0] control the direction of the
associated port pin. Port Alternate Function operation overrides the Data Direction Regis-
ter setting.
If the value of the bit is 0, the direction is output, and data in the Port A–C Output Data
registers is driven onto the port pin.
If the value of the bit is 1, the direction is input. The port pin is sampled, the value is writ-
ten into the Port A–C Input Data registers, and the output driver is tristated.
Table 18. Port A–C Data Direction Sub-Registers
BITS
FIELD
RESET
R/W
7
DD7
6
DD6
5
DD5
4
DD4
3
DD3
2
DD2
1
DD1
0
DD0
1
1
1
1
1
1
1
1
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
If 01H in Port A–C Address Register, accessible through the Port A-C Control Register
ADDR
Bit
Value
(H)
Description
Position
[7:0]
These bits control the direction of the associated port pin. Port Alternate Function
operation overrides the Data Direction register setting.
Data
Direction
0
1
Output. Data in the Port A–C Output Data register is driven onto the port pin.
Input. The port pin is sampled and the value written into the Port A–C Input Data
Register. The output driver is tristated
Port A–B Alternate Function 0 Subregisters
The Port A–B Alternate Function subregisters, shown in Table 19, are accessed through
the Port A–B Control registers by writing 02hto the Port A–B Address registers. The Port
A–B Alternate Function subregisters select the alternate functions for the selected pins.
Refer to the GPIO Alternate Functions section on page 36 to determine the alternate func-
tion associated with each port pin.
Do not enable alternate function for GPIO port pins which do not have an associated al-
ternate function. Failure to follow this guideline may result in unpredictable operation.
Caution:
General-Purpose I/O
P R E L I M I N A R Y
PS024604-1005
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