80CL31 Datasheet, PDF (16/40 Pages) NXP Semiconductors – Low-voltage single-chip 8-bit microcontrollers

Philips Semiconductors
Low-voltage single-chip 8-bit microcontrollers
Product specification
80CL31/80CL51
Timer 1
Overflow
÷2
SMOD = 1
Write
to
SBUF
80CL51 Internal Bus
TB8
DS Q
CL
SBUF
Zero Detector
÷ 16
Serial
Port
Interrupt
Sample
1-to-0
Transition
Detector
RxD
Start
TX Clock
Shift
TX Control
T1
Data
Send
÷ 16
Start
RX Clock RI
RX Control
Load
SBUF
Shift
Bit Detector
Load
SBUF
Input Shift Register
(9 Bits)
Shift
S0 BUFFER
Read
SBUF
TX
Clock
80CL51 Internal Bus
Write to SBUF
Data
Shift
Send
S1P1
TxD
Start Bit
D0
D1
D2
D3
TI
RX
Clock
÷ 16 Reset
R
e
RxD
c
Bit Detector
e
Sample Time
i
v
Shift
e
Start
Bit
D0
D1
D2
D3
RI
D4
D5
D6
D7
D4
D5
D6
D7
January 1995
Figure 8. Serial Port Mode 1
16
TxD
T
r
a
n
s
m
i
t
Stop Bit
Stop Bit