![](http://datasheet.mmic.net.cn/330000/MB90P224A_datasheet_16438134/MB90P224A_41.png)
41
MB90220 Series
4. UART0
UART0 is a serial I/O port for synchronous or asynchronous communication with external resources. It has the
following features:
Full duplex double buffer
CLK synchronous and CLK asynchronous data transfers capable
Multiprocessor mode support (Mode 2)
Built-in dedicated baud-rate generator (12 rates)
Arbitrary baud-rate setting from external clock input or internal timer
Variable data length (7 to 9 bits (without parity bit); 6 to 8 bits (with parity bit))
Error detection function (Framing, overrun, parity)
Interrupt function (Two sources for transmission and reception)
Transfer in NRZ format
The MB90220 has three of these modules on chip.
(1) Register Configuration
000020
H
000024
H
000028
H
PEN
SBL
MC1
MC0
SMDE
RFC
SCKE
bit7
bit6
bit5
bit4
bit3
bit2
bit1
SOE
bit0
000022
H
000026
H
00002A
H
D7
D6
D5
D4
D3
D2
D1
D0
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
000021
H
000025
H
000029
H
(R)
(R)
(R)
(R)
(R)
(R/W)
(R/W)
(R)
RDRF
ORFE
PE
TDRE
RIE
TIE
RBF
TBF
000023
H
000027
H
00002B
H
BCH
RC3
RC2
RC1
RC0
BCH0
P
D8
UMC0
UMC1
UMC2
USR0
USR1
USR2
00000100
B
00001000
B
UIDR0/UODR0
UIDR1/UODR1
UIDR2/UODR2
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
XXXXXXXX
B
URD0
URD1
URD2
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
0000000X
B
Register name Address
Serial mode control register
Register name Address
Register name Address
Register name Address
Initial value
Initial value
Initial value
Initial value
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
(R/W)
Mode Control Register 0 to 2 (UMC0 to 2)
Status Register 0 to 2 (USR0 to 2)
Input Data Register 0 to 2 (UIDR0 to 2)/Ouput Data Register 0 to 2 (UODR0 to 2)
Rate and Data Register 0 to 2 (URD0 to 2)
00002C
H
(—)
(—)
(—)
(R/W)
(R/W)
(R/W)
(—)
(—)
—
—
—
CTE
CSP
CTSE
—
—
UCCR
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
- - - 000 - -
B
Register name Address
Initial value
UART CTS Control Register (UCCR)