M16C/62 Group DATASHEET

Timers’ functions for three-phase motor controlMitsubishi microcomputersM16C / 62 GroupSINGLE-CHIP 16-BIT CMOS MICROCOMPUTERFigure 1.18.5 shows the block diagram for three-phase waveform mode. In three-phase waveform mode,______the positive-phase waveforms (U phase, V phase, and W phase) and negative waveforms (U phase, V___phase, and W phase), six waveforms in total, are output from P80, P81, P72, P73, P74, and P75 as active___on the “L” level. Of the timers used in this mode, timer A4 controls the U phase and U phase, timer A1______controls the V phase and V phase, and timer A2 controls the W phase and W phase respectively; timer B2controls the periods of one-shot pulse output from timers A4, A1, and A2.In outputting a waveform, dead time can be set so as to cause the “L” level of the positive waveform___output (U phase, V phase, and W phase) not to lap over the “L” level of the negative waveform output (U______phase, V phase, and W phase).To set short circuit time, use three 8-bit timers sharing the reload register for setting dead time. A valuefrom 1 through 255 can be set as the count of the timer for setting dead time. The timer for setting deadtime works as a one-shot timer. If a value is written to the dead timer (034C16), the value is written to thereload register shared by the three timers for setting dead time.Any of the timers for setting dead time takes the value of the reload register into its counter, if a starttrigger comes from its corresponding timer, and performs a down count in line with the clock sourceselected by the dead time timer count source select bit (bit 2 at 034916). The timer can receive anothertrigger again before the workings due to the previous trigger are completed. In this instance, the timerperforms a down count from the reload register’s content after its transfer, provoked by the trigger, to thetimer for setting dead time.Since the timer for setting dead time works as a one-shot timer, it starts outputting pulses if a triggercomes; it stops outputting pulses as soon as its content becomes 0016, and waits for the next trigger tocome.______The positive waveforms (U phase, V phase, and W phase) and the negative waveforms (U phase, V___phase, and W phase) in three-phase waveform mode are output from respective ports by means ofsetting “1” in the output control bit (bit 3 at 034816). Setting “0” in this bit causes the ports to be the stateof set by port direction register. This bit can be set to “0” not only by use of the applicable instruction, but_______by entering a falling edge in the NMI terminal or by resetting. Also, if “1” is set in the positive and negativephases concurrent L output disable function enable bit (bit 4 at 034816) causes one of the pairs of U___ ___ ___phase and U phase, V phase and V phase, and W phase and W phase concurrently go to “L”, as a result,the port become the state of set by port direction register.104