System Description
Designer Reference Manual
DRM028 — Rev 0
18
System Description
MOTOROLA
2.3.1 Software Specification
The application software is practically the same for all three hardware
platforms. The only modification needed is to include one of three
constants that customize the hardware and motor parameter settings.
The software (written in C language) specifications are listed in
Table 2-1
. A useful feature of the software is serial communication with
PC master software protocol via RS232. The PC master software is PC
computer software which allows reading and setting of all the system
variables, and can also run html script pages to control the application
from the PC. Another feature of the BLDC control software, is on-line
parameter modification with PC master software, which can be used for
software parameter tuning to a customer motor.
.
Table 2-1. Software Specifications
Control Algorithm
3-phase trapezoidal BLDC motor control star or delta!
connected
Sensorless, with back-EMF zero crossing commutation
control
Speed closed loop control
Motoring mode
Target Processor
MC68HC908MR32
Language
C-language with some arithmetical functions in assembler
Compiler
Metrowerks ANSI-C/cC++ Compiler for HC08
Application
Control
Manual interface (start/stop switch, speed potentiometer
control, LED indication)
PC master software (remote) interface (via RS232 using PC
computer)
MCU Oscillator
Frequency
4 MHz (with default software setting)
MCU Bus
Frequency
8 MHz (with default software setting)
Minimal BLDC
Motor
Commutation
Period
(Without PC
Master
Software
Communication)
333
µ
s (with default software setting and COEF_HLFCMT =
0.450)
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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