Sharp LC-30HV2E, Service Manual

Page: 36 / 173

36
LC-30HV2E
Ë
VHiSDA5550M-1 (ASSY: IC1601)
»
Stereo Audio DAC
»
Block Diagram
99, 1, 3, 4, 2, 100,
98, 96
97, 94, 93, 89, 86,
84, 82, 79, 81, 83,
90, 85, 77, 78, 76,
71, 69
70, 68, 67
9, 10, 11, 12, 13,
14, 15, 16
41, 42, 43, 44, 45,
46, 47, 62
24, 25, 26, 27
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Pin Function
Pin No. Pin Name I/O Pin Function
D0-D7
A0-A16
A17-A19/
P4.0, P4.1, P4.4
P0.0-P0.7
P1.0-P1.7
(PWM)
P2.0-P2.3
(ADC)
I/O
O
I/O
I/O
I/O
I
Data bus for external memory or data RAM.
Address bus for external program memory or data RAM.
After power-on P4.0,P4.1,P4.4 work as additional address lines A17…A19.
In port mode, these port lines act as bi-directional I/O port with internal pull-up
resistors. Port pins that have ‘1’ written to them are pulled high by the internal pull-up
resistors and in that state can be used as inputs.
Port 0 is a 8-bit open drain bi-directional I/O-port. Port 0 pins that have 1 written to
them float: in this state they can be used as high impedance inputs.
Port is a 8-bit bi-directional multifunction I/O port with internal pull-up resistors. Port 1
pins that have 1 written to them are pulled high by the internal pull-up resistors and in
that state can be used as inputs.
The secondary functions of port 1 pins are:
Port bits P1.0-P1.5 contain the 6 output channels of the 8-bit pulse width modulation
unit.
Port bits P1.6-P1.7 contain the two output channels of the 14-bit pulse width
modulation unit.
Port 2 is a 4-bit input port without pull-up resistors.
Port 2 also works as analog input for the 4-channel-ADC.