M16C User Manual.pdf

S I/O3, 4Mitsubishi microcomputersM16C / 62 GroupSINGLE-CHIP 16-BIT CMOS MICROCOMPUTERS I/Oi control register (i = 3, 4) (Note 1)b7 b6 b5 b4 b3 b2 b1 b0Symbol Address When resetSiC 036216, 036616 4016BitsymbolBit nameDescriptionRWSMi0SMi1SMi3SMi5SMi6SMi7Internal synchronousclock select bitS I/Oi port select bit(Note 2)Transfer direction selectbitSynchronous clockselect bit (Note 2)SOUTi initial valueset bitb1 b00 0 : Selecting f10 1 : Selecting f81 0 : Selecting f321 1 : Not to be usedSMi2 SOUTi output disable bit 0 : SOUTi output1 : SOUTi output disable(high impedance)0 : Input-output port1 : SOUTi output, CLK functionNothing is assigned.In an attempt to write to this bit, write “0”. The value, if read, turns out to be “0”.0 : LSB first1 : MSB first0 : External clock1 : Internal clockEffective when SMi3 = 00 : L output1 : H outputNote 1: Set “1” in bit 2 of the protection register (000A16) in advance to write to theS I/Oi control register (i = 3, 4).Note 2: When using the port as an input/output port by setting the SI/Oi portselect bit (i = 3, 4) to “0”, be sure to set the sync clock select bit to “1”.SI/Oi bit rate generatorb7 b0 Symbol Address When resetS3BRG 036316 IndeterminateS4BRG 036716 IndeterminateIndeterminateAssuming that set value = n, BRGi divides the countsource by n + 1Values that can be set0016 to FF16R WSI/Oi transmit/receive registerb7 b0 Symbol Address When resetS3TRR 036016 IndeterminateS4TRR 036416 IndeterminateIndeterminateTransmission/reception starts by writing data to this register.After transmission/reception finishes, reception data is input.RWFigure 1.19.32. S I/O3, 4 related register150