Functional Description
14-32
ADSP-BF50x Blackfin Processor Hardware Reference
Conversely, if the
PWM_SRMODE
bit is low and SR mode is enabled, the
PWM_SR
bit of
PWM_STAT
register is cleared.
Since this is a software programmable bit, be careful not to write it
to an active state in a non-SR mode system and cause
shoot-through at the power inverters, possibly leading to an unsafe
situation.
In the typical power converter configuration for switched or variable
reluctance motors, the motor winding is connected between the two
power switches of a given inverter leg. Therefore, to allow for a complete
circuit in the motor winding, it is necessary to turn on both switches at
the same time.
SR mode provides four mode types: hard chop, alternate chop, soft
chop-bottom on, and soft chop-top on (see
Table 14-2
). Three registers
(
PWM_CHAL
,
PWM_CHBL
, and
PWM_CHCL
) are used to define edge placement of
the low side of the channel. The
PWM_DT
register, which is not used, is
internally forced to 0 by hardware when SR mode is active. The four
switched reluctance (SR) chop modes are specified via three bits
(
PWM_SR_LSI_A
,
PWM_SR_LSI_B
, and
PWM_SR_LSI_C
) of the
PWM_LSI
register,
full on mode, and full off mode.
The
PWM_CHA
and
PWM_CHAL
registers are programmed independently;
PWM_CHA
specifies edge placement for the high side of the channel, and
PWM_CHAL
specifies edge placement for the low side of the channel.
Similarly, the
PWM_CHB
and
PWM_CHBL
pair, and the
PWM_CHC
and
PWM_CHCL
pair, respectively, specify high-side and low-side edge placement.
Summary of Contents for EZ-KIT Lite ADSP-BF506F
Page 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Page 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...