UPD78320 Datasheet, PDF (39/88 Pages) NEC – 16/8-BIT SINGLE-CHIP MICROCONTROLLER

Figure 3-6. Asynchronous Serial Interface Block Diagram
Internal Bus
RXB Receive Buffer
ASIM
RXE PS1 PS0 CL SL SCK
BRG
BRGM
ASIS
TXS
RXD
Shift Register
PE FE OVE
Shift Register
1 ^Match
2
Clear
TXD
Receive
Control
Parity
Check
INTSR
Send Control
INTSER
Parity
Addition
INTST
fCLK/8
1
1
16
16
Send/Receive Baud Rate Generator Output
fCLK/4
Baud Rate Generator