UPD784938 Datasheet, PDF (430/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

Figure 18-2. Asynchronous Serial Interface Block Diagram
1/8
1/8
RXB, RXB2
Serial receive
buffer
Internal bus
1/8
TXE RXE PS1 PS0 CL
TXE2 RXE2 PS21 PS20 CL2
ASIM, ASIM2
SL ISRM SCK
SL2 ISRM2 SCK2
RESET
P30/RXD,
P13/RXD2
P31/TXD,
P14/TXD2
P25/ASCK,
P12/ASCK2
Shift register
ASIS, ASIS2
PE FE OVE
PE2 FE2 OVE2
RESET
Serial transmit TXS,
shift register TXS2
Reception
control
parity check
INTSR, INTSR2
1
m
INTSER,
INTSER2
Transmission
control parity
addition
INTST,
INTST2
Baud rate generator
1
m
1
2ⁿ
Selector
fXX