Analog Devices ADSP-SC58 Series Hardware Reference Manual page 583

Figure 14-5: GPIO Programming Model Flow (Part 2)
ADSP-SC58x/ADSP-2158x SHARC+ Processor Hardware Reference
A
4
OPEN DRAIN
WRITE PORT_DATA_CLR
FOR REQUIRED PINS
WRITE PORT_INEN_SET TO SET
APPROPRIATE BITS TO ENABLE
THE INPUT DRIVERS
TO INVERT THE POLARITY OF
NOT ACTIVE
ACTIVE ACTIVE OR
NOT ACTIVE
STATE
WRITE PORT_DIR_ SET
WRITE PORT_DIR_ CLR
TO SET APPROPRIATE PINS AS
TO SET APPROPRIATE PINS AS
OUTPUTS AND ENTER ACTIVE INPUTS AND ENTER NOT ACTIVE
STATE (LOGIC 0) STATE (LOGIC 1 )
YES
CHANGE
STATE
NO
DONE
3
INPUT OR
INPUT
OPEN DRAIN**
PIN POLARITY
INVERTED*
YES
WRITE PINT_INV_CLR
WRITE PINT_INV_SET
TO DISABLE THE INVERTERS ON
THE APPROPRIATE PINS THE APPROPRIATE PINS
WRITE PORT_DIR_CLR
TO SET APPROPRIATE
PINS AS INPUTS
YES
INTERRUPT
ABILITY
WRITE PORT_INEN_SET TO SET
APPROPRIATE BITS TO ENABLE
THE INPUT DRIVERS
DONE
B
PORT Programming Model
NO
NO
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