AN2841 Freescale Semiconductor / Motorola, AN2841 Datasheet - Page 7

• Manufacturer Part Number: AN2841
• Description: Using the Hall Decoder (HD) eTPU Function
• Manufacturer: Freescale Semiconductor / Motorola

3.2
The HD function has optional support for commutation capability using the PWMC function. The user
should create 1, 2, 3, or 4 commutation tables according to the number of HD phases and pass their pointers
to the HD initialization function.
When an edge of any input Hall sensor signal is detected, a commutation command to one or more PWMC
phases is sent, and then the sector value is changed.
The commutation tables must be defined as structures of uint32_t. Each phase’s commutation table
consists of eight commutation commands. Each table entry is one commutation command.
The order of table entries is as follows:
1) Commutation command to execute on LH transition, on incremental direction, as first (lh_i_0).
2) Commutation command to execute on LH transition, on incremental direction, as second (lh_i_1).
3) Commutation command to execute on LH transition, on decremental direction, as first (lh_d_0).
4) Commutation command to execute on LH transition, on decremental direction, as second (lh_d_1).
5) Commutation command to execute on HL transition, on incremental direction, as first (hl_i_0).
6) Commutation command to execute on HL transition, on incremental direction, as second (hl_i_1).
Freescale Semiconductor
Hall Sensor Signal
Hall Sensor Signal
Hall Sensor Signal
Hall Sensor Signal
Commutation
Sector
Figure 9. Pre-Defined Configurations: Four Phases - by 90 and 45 Deg
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Using the Hall Decoder (HD) eTPU Function, Rev. 0
D
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1000
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0011
0100
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Function Description
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