Analog Devices ADSP-SC58 Series Hardware Reference Manual page 957

Programming Model for Three-Phase AC Motor Control
Figure 19-27: PWM System States
As shown in the state diagram, the module configuration is updated on state transitions (indicated by the arrows).
The transitions are initialization, motor start, PWM sync interrupt request (on each), and motor stop. The follow-
ing sections discuss the transitions in detail.
•
PWM Initialization for Motor Control
•
PWM Enable for Motor Control
•
PWM Response to Sync Interrupt for Motor Control
•
PWM Disable (and Stop the Motor) for Motor Control
PWM Initialization for Motor Control
The processor must program the PWM at power-up as follows and repeat this programming to bring the PWM and
the system into a known (safe) state.
1. Place the PWM module in a safe state and set up synchronization of the module using the following bitwise
operations on the PWM_CTL
PWM_CTL &= 0xFFE0FF08
PWM_CTL |= 0x20000
PWM_CHANCFG &= 0x80808080
PWM_CHANCFG |= 0x24242424
These operations result in the following bit settings:
• Disable PWM (PWM_CTL.GLOBEN =0)
• Disable delay for channels A, B, C, D (PWM_CTL.DLYAEN through PWM_CTL.DLYDEN =0). All pha-
ses must run with same phase.
• Use internal synchronization by timer TMR0 (PWM_CTL.EXTSYNC =0, PWM_CTL.EXTSYNCSEL
=1)
• The same timer, TMR0 (PWM_CTL.INTSYNCREF = b#000) synchronizes all phases.
19–36
MOTOR STOPPED
STOP PWM
MOTOR RUNNING
and PWM_CHANCFG registers:
ADSP-SC58x/ADSP-2158x SHARC+ Processor Hardware Reference
INIT PWM
ENABLE PWM
PWM SYNC IRQ