M16C User Manual.pdf

Clock asynchronous serial I/O (UART) modeMitsubishi microcomputersM16C / 62 GroupSINGLE-CHIP 16-BIT CMOS MICROCOMPUTERTable 1.19.7 lists the functions of the input/output pins during UART mode. This table shows the pin_______ _______functions when the separate CTS/RTS pins function is not selected. Note that for a period from when theUARTi operation mode is selected to when transfer starts, the TxDi pin outputs a “H”. (If the N-channelopen-drain is selected, this pin is in floating state.)Table 1.19.7. Input/output pin functions in UART modePin name Function Method of selectionTxDi(P63, P67, P70)Serial data outputRxDi(P62, P66, P71)CLKi(P61, P65, P72)CTSi/RTSi(P60, P64, P73)Serial data inputProgrammable I/O portTransfer clock inputCTS inputRTS outputPort 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)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)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”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”________ _______(when separate CTS/RTS pins function is not selected)132