M16C30L Datasheet, PDF (114/166 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Clock asynchronous serial I/O (UART) mode
Mitsubishi microcomputers
M16C / 30L Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Table 1.16.7 lists the functions of the input/output pins during UART mode. Note that for a period from
when the UARTi operation mode is selected to when transfer starts, the TxDi pin outputs an “H”. (If the N-
channel open-drain is selected, this pin is in floating state.)
Table 1.16.7. Input/output pin functions in UART mode
Pin name
Function
TxDi
Serial data output
(P63, P67, P70)
Method of selection
RxDi
Serial data input
(P62, P66, P71)
Port P62, P66 and P71 direction register (bits 2 and 6 at address 03EE16,
bit 1 at address 03EF16)= “0”
(Can be used as an input port when performing transmission only)
CLKi
Programmable I/O port
(P61, P65, P72) _{Transfer clock input}
Internal/external clock select bit (bit 3 at address 03A016, 03A816, 037816) = “0”
Internal/external clock select bit (bit 3 at address 03A016, 03A816) = “1”
Port P61, P65 direction register (bits 1 and 5 at address 03EE16) = “0”
(Do not set external clock for UART2)
CTSi/RTSi
CTS input
(P60, P64, P73)
CTS/RTS disable bit (bit 4 at address 03A416, 03AC16, 037C16) =“0”
CTS/RTS function select bit (bit 2 at address 03A416, 03AC16, 037C16) = “0”
Port P60, P64 and P73 direction register (bits 0 and 4 at address 03EE16,
bit 3 at address 03EF16) = “0”
RTS output
CTS/RTS disable bit (bit 4 at address 03A416, 03AC16, 037C16) = “0”
CTS/RTS function select bit (bit 2 at address 03A416, 03AC16, 037C16) = “1”
Programmable I/O port CTS/RTS disable bit (bit 4 at address 03A416, 03AC16, 037C16) = “1”
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