ez80f91 ZiLOG Semiconductor, ez80f91 Datasheet - Page 156

• Manufacturer Part Number: ez80f91
• Description: Ez80 Acclaimplus!? Connectivity Assp Ez80f91 Assp
• Manufacturer: ZiLOG Semiconductor

PS027001-0707
Note:
PWM Master Mode
Modification of Edge Transition Values
Table 71. Example: Multi-PWM Addressing
In PWM Master mode, the pair of output signals generated from the PWM0 generator
(PWM0 and PWM0) are directed to all four sets of PWM output pairs. Setting
TMR3_PWM_CTL1[MM_EN] to 1 enables PWM Master mode. Assuming the outputs
are all enabled and no AND/OR gating is used, all four PWM output pairs transition
simultaneously under the direction of PWM0 and PWM0. In PWM Master mode,
the outputs still be gated individually using the AND/OR gating functions described in the
next section. Multi-PWM mode and the individual PWM outputs must be enabled along
with PWM Master mode. It is possible to enable or disable any combination of the 4 PWM
outputs while running in PWM Master mode.
Special circuitry is included for the update of the PWM edge transition values. Normal use
requires that these values be updated while the PWM generator is running.
Under certain circumstances, electric motors driven by the PWM logic encounters rough
operation. In other words, cycles are skipped if the PWM waveform edge is not carefully
modified.
Without special consideration, if a PWM generator looks for a particular count to make a
state transition and if the edge transition value changes to a value that already occurred in
Parameter
Timer Reload Value
PWM0 rising edge
PWM0 falling edge
PWM1 rising edge
PWM1 falling edge
PWM enable
PWM0 enable
PWM1 enable
Multi-PWM enable
Prescaler Divider = 4
PWM nonoverlapping delay = 0 TMR3_PWM_CTL2[PWM_DLY]
Control Register(s)
{TMR3_RR_H, TMR3_RR_L}
{TMR3_PWM0R_H,
TMR3_PWM0R_L}
{TMR3_PWM0F_H, TMR3_PWM0F_L} 0004h
{TMR3_PWM1R_H,
TMR3_PWM1R_L}
{TMR3_PWM1F_H, TMR3_PWM1F_L} 0007h
TMR3_PWM_CTL1[PAIR_EN]
TMR3_PWM_CTL1[PWM0_EN]
TMR3_PWM_CTL1[PWM1_EN]
TMR3_PWM_CTL1[MPWM_EN]
TMR3_CTL[CLK_DIV]
Programmable Reload Timers
Product Specification
eZ80F91 ASSP
Value
000Ch
0008h
0006h
1
1
1
1
00b
0000b
148