M30222 Datasheet, PDF (104/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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Specifications in this manual are tentative and subject to change
MITSUBISHI MICROCOMPUTERS
M30222 Group
Rev. G
Serial Communications
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Serial Communications
The five channels of serial communication that are available are: UART0, UART1, UART2, SI/O3 and
SI/O4.
UART0 to 2
UART0, UART1 and UART2 have exclusive timers to generate the transfer clock, so each operates
independently from the others.
UARTi (i = 0 to 2) has two operation modes: a clock synchronous serial I/O mode and a clock asynchro-
nous serial I/O mode (UART mode). The contents of the serial I/O mode select bits (bits 0 to 2 at
addresses 03A016, 03A816 and 037816) determine whether UARTi is used as a clock synchronous serial
I/O or as a UART.
UART0 through UART2 are almost equal in their functions with minor exceptions. UART2 is compliant
with the Subscriber Identity Module (SIM) interface with some extra settings added in clock-asynchro-
nous serial I/O mode. It also has the bus collision detection function that generates an interrupt request
if the TxD pin and the RxD pin are different in level. UART2 also provides support for both I²C and SPI
transfer formats.
Figure 1.78 shows the block diagram of UART0, UART1 and UART2. Figures 1.79 and 1.80 show the
block diagram of the transmit/receive unit. Figures 1.81 to 1.86 show the registers related to UARTi.
Table 1.33 shows the comparison of functions of UART0 through UART2.
Table 1.33. Comparison of functions of UART0 through UART2
Function
CLK polarity selection
LSB first/MSB first selection
Continuous receive mode selection
Transfer clock output from multiple
pins selection
Separate CTS/RTS pins
Serial data logic switch
Sleep mode selection
TxD, RxD I/O polarity switch
TxD, RxD port output format
Parity error signal output
Bus collision detection
I²C
SPI
UART0
Supported (Note 1)
Supported (Note 1)
Supported (Note 1)
Not supported
Supported
Not supported
Supported (Note 3)
Not supported
CMOS or N-channel
open drain
Not supported
Not supported
Not supported
Not supported
UART1
Supported (Note 1)
Supported (Note 1)
Supported (Note 1)
Supported (Note 1)
Not supported
Not supported
Supported (Note 3)
Not supported
CMOS or N-channel
open drain
Not supported
Not supported
Not supported
Not supported
UART2
Supported (Note 1)
Supported (Note 2)
Supported (Note 1)
Not supported
Not supported
Supported (Note 4)
Not supported
Supported
N-channel open drain
output (Note 5)
Supported (Note 4)
Supported
Supported
Supported
Note 1: Only in Clock Synchronous Serial I/O mode.
Note 2: Only in Clock Synchronous Serial I/O mode and 8-bit UART mode.
Note 3: Only in UART mode.
Note 4: Using SIM interface.
Note 5: Input and output when using SIM interface for UART2 only.
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