M16C User Manual.pdf

A-D ConverterMitsubishi microcomputersM16C / 62 GroupSINGLE-CHIP 16-BIT CMOS MICROCOMPUTER(1) One-shot modeIn one-shot mode, the pin selected using the analog input pin select bit is used for one-shot A-D conversion.Table 1.20.2 shows the specifications of one-shot mode. Figure 1.20.4 shows the A-D control registerin one-shot mode.Table 1.20.2. One-shot mode specificationsItemSpecificationFunctionThe pin selected by the analog input pin select bit is used for one A-D conversionStart conditionWriting “1” to A-D conversion start flagStop condition• End of A-D conversion (A-D conversion start flag changes to “0”, exceptwhen external trigger is selected)• Writing “0” to A-D conversion start flagInterrupt request generation timing End of A-D conversionInput pinOne of AN0 to AN7, as selectedReading of result of A-D converter Read A-D register corresponding to selected pinA-D control register 0 (Note 1)b7 b6 b5 b4 b3 b2 b1 b0 Symbol Address When reset0 0ADCON0 03D616 00000XXX2Bit symbol Bit name FunctionCH0CH1CH2MD0MD1TRGAnalog input pin selectbitA-D operation modeselect bit 0Trigger select bitb2 b1 b00 0 0 : AN0 is selected0 0 1 : AN1 is selected0 1 0 : AN2 is selected0 1 1 : AN3 is selected1 0 0 : AN4 is selected1 0 1 : AN5 is selected1 1 0 : AN6 is selected1 1 1 : AN7 is selected (Note 2)b4 b30 0 : One-shot mode (Note 2)0 : Software trigger1 : ADTRG triggerR W ADST A-D conversion start flag 0 : A-D conversion disabled1 : A-D conversion startedCKS0 Frequency select bit 0 0: fAD/4 is selected1: fAD/2 is selectedNote 1: If the A-D control register is rewritten during A-D conversion, the conversionresult is indeterminate.Note 2: When changing A-D operation mode, set analog input pin again.A-D control register 1 (Note)b7 b6 b5 b4 b3 b2 b1 b010Symbol Address When resetADCON1 03D716 0016Bit symbol Bit nameSCAN0 A-D sweep pinselect bitSCAN1Figure 1.20.4. A-D conversion register in one-shot modeMD2FunctionInvalid in one-shot modeBITS 8/10-bit mode select bit 0 : 8-bit mode1 : 10-bit modeCKS1VCUTOPA0OPA1A-D operation modeselect bit 1Frequency select bit1Vref connect bitExternal op-ampconnection mode bit0 : Any mode other than repeat sweepmode 10 : fAD/2 or fAD/4 is selected1 : fAD is selected1 : Vref connectedb7 b60 0 : ANEX0 and ANEX1 are not used0 1 : ANEX0 input is A-D converted1 0 : ANEX1 input is A-D converted1 1 : External op-amp connection modeNote: If the A-D control register is rewritten during A-D conversion, the conversionresult is indeterminate.R W157