VCT 38xxA
ADVANCE INFORMATION
5.18.5.Audio Ports P42 to P46
5.18.5.1. Features
– analog audio input or output
– digital input port
The analog audio ports AIN1−3, AOUT1−2 can alter-
natively be used as digital input ports. To activate the
audio function of the port pin, the corresponding MOD
flag has to be set to Special mode. In Normal mode the
port pin serves as digital input. After reset the audio
ports are in Normal mode.
– Schmitt trigger input buffer
– special input function
VDD
P4D read
DBy
VSS
Special In 4.y
Audio
1
P4.y
0
Q
D
P4M
y: Port pin number 2 to 6
Fig. 5–7: Audio port circuit
AINxD
AINx Data Input
r:
Read pin level resp. data latch.
AOUTxD
AOUTx Data Input
r:
Read pin level resp. data latch.
To use the Audio ports as software input, the corre-
sponding flags must be programmed to Normal Input
mode.
AINxM
w1:
w0:
AINx Normal/Special Mode Flag
Special Audio Input Mode
Normal Input Mode
AOUTxM AOUTx Normal/Special Mode Flag
w1:
w0:
Special Audio Output Mode
Normal Input Mode
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Micronas