W921E840A Datasheet, PDF (10/58 Pages) Winbond – 4-BIT MICROCONTROLLER

5. BLOCK DIAGRAM
W921E840A/W921C840
OSCI
OSCO
XT
XT
RESET
V_DD
V_SS
W Reg. V Reg.
Co-V
Reg.
U Reg.
Co-U
Reg.
Program
Counter
EPROM
8K x 10
Decoder and
Control
Circuit
Stack
Pointer
Oscillator
and
System
Control
Prescaler
B Reg.
A Reg.
ALU
RAM
512 x 4
Port Mode
Register
Timer 0
Timer 1
Timer 2
Timer 3
MUX
(ANI0 to ANI3)
+
-
P5.2/VREF or
P5.3/DAOUT
MUX
Port P2
Port P3
Port P4
Port P5
Port P6
Port PA
Port PB
Port PC
Port PD
DTMF
Generator
Beep Tone
Generator
D/A Convertor
D/A MSB D/A LSB
P2.0-P2.3
P3.0-P3.3
P4.0-P4.3
P5.0-P5.3
P6.0-P6.3
PA.0-PA.3
PB.0-PB.3
PC.0-PC.3
PD.0-PD.1
DTMF
BTG
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