SH7101 datasheet(408/560 Pages) RENESAS

408 / 560 page

Section 13 Motor Management Timer (MMT)

Rev.1.00 Sep. 18, 2008 Page 374 of 522

REJ09B0069-0100

The values of TBRU to TBRW should always be set in the range H'0000 to H'FFFF – 2Td, and the

value of TPBR should always be set in the range H'0000 to H'FFFF – 4Td.

(4) PWM Output Active Level Setting

In the operating modes, the active level of PWM pulses is set with bits OLSN and OLSP in the

timer mode register (TMDR).

The output level can be set for the three positive phases and the three negative phases of six-phase

output. The operating mode must be exited before setting or changing the output level.

(5) Dead Time Setting

In the operating modes, PWM pulses are output with a non-overlap relationship between the

positive and negative phases. This non-overlap time is known as the dead time. The non-overlap

time is set in the timer dead time data register (TDDR). The dead time generation waveform is

generated by comparing the value set in TDDR with the timer dead time counters (TDCNT) for

each phase. The operating mode must be exited before changing the contents of TDDR.

(6) PWM Period Setting

In the operating modes, 1/2 the PWM pulse period is set in TPBR. The TPBR value should always

be set in the range H'0000 to H'FFFF – 4Td. The value set in TPBR is transferred to TPDR at the

timing selected with bits MD1 and MD0 in the timer mode register (TMDR). After the transfer,

the value in TPDR is {TPBR value + 2Td}.

The new PWM period is effective from the next period when data is updated at the TCNT counter

peak, and from the same period when data is updated at the trough.

(7) Register Updating

In the operating modes, buffer registers are used to update compare register data. Update data can

be written to a buffer register at all times. The buffer register value is transferred to the compare

case of a write to the free operation address for TBRU to TBRW, in which case the value is

transferred to the corresponding compare register immediately).

(8) Initial Output in Operating Modes

The initial output in the operating modes is determined by the initial values of TBRU to TBRW.

Table 13.2 shows the relationship between the initial value of TBRU to TBRW and the initial

output.

SH7101 Datasheet(PDF) 408 Page - Renesas Technology Corp