AN2514 Freescale Semiconductor / Motorola, AN2514 Datasheet - Page 18

• Manufacturer Part Number: AN2514
• Description: 3-Phase Sine Wave Generator TPU Function Set
• Manufacturer: Freescale Semiconductor / Motorola

AN2514/D
Synchronized Change
of PWM Prescaler
And Synchronization
Signal Prescaler
Host Interface
18
The 3Sin_sync TPU function actually uses the presc_copy parameter instead
of the prescaler parameter. The prescaler parameter holds the prescaler value
that is copied to the presc_copy by the 3Sin_bottom function at the time the
PWM parameters are reloaded. This ensures that new prescaler values for the
PWM signals, as well as the synchronization signal, are applied at the same
time. Write the synchronization signal prescaler parameter address to the
sync_presc_addr parameter to enable this mechanism. Write 0 to disable it,
and remember to set the synchronization signal presc_copy parameter instead
of the prescaler parameter in this case.
move > 0
move > 0
prescaler = 1
prescaler = 1
move < 0
move < 0
prescaler = 2
prescaler = 2
3-Phase Sine Wave Generator TPU Function Set (3Sin)
3
Freescale Semiconductor, Inc.
2
For More Information On This Product,
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Written By CPU
Written By TPU
1
1
Figure 7. Synchronization signal adjustment examples
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0
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pw
pw
Channel Function Select
Channel Priority
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Name
pw
pw
Table 11. 3Sin_sync Control Bits
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3Sin_sync function number
00 – Channel Disabled
01 – Low Priority
10 – Middle Priority
11 – High Priority
(Assigned during assembly the
DPTRAM code from library TPU
functions)
Written by both CPU and TPU
Not Used
Options
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MOTOROLA