参数资料
型号: DM300014
厂商: Microchip Technology
文件页数: 39/72页
文件大小: 0K
描述: BOARD DEMO DSPICDEM 1.1 GEN PURP
标准包装: 1
Demonstration Program Operation
3.4.2
Main Loop Code Execution
The step-by-step Main Loop execution sequence is shown in Table 3-4.
TABLE 3-4:
Seq
MAIN LOOP CODE EXECUTION SEQUENCE
Program Task
1
2
3
4
5
6
7
8
9
10
11
12-bit ADC collects 256 samples from the digital potentiometer output on AN3 into
a RAM buffer.
Buffered data set is filtered using an IIR filter to remove line noise. The filter can
be changed to an FIR filter or no filter from the DSP menu options. The filtering
operation is benchmarked using the Timer4/5 pair.
A complex in-place 256-point FFT is performed on the filtered data set, resulting
in complex frequency data (x + jy). This operation is benchmarked using the
Timer4/5 pair.
Squared magnitude is computed for each frequency bin in an in-place fashion
(x 2 + y 2 ).
The magnitude data is run through a routine that returns the frequency bin and
magnitude of the largest element.
The magnitude of the largest element is compared against a threshold and
captured if it is greater than the threshold so that low-level noise does not show
up as a frequency estimate. (Provides a simplified peak-detection algorithm.)
The ADC settings are changed to sample pins AN4 (RP2), AN5 (RP3), AN6
(RP1) and AN8 (temperature sensor U9). One sample of each is recorded and
the ADC is reconfigured for the initial settings.
If a Timer3 count has expired, a software flag is set to inform the CPU that the
results recorded may now be displayed. This ensures that the CPU refreshes the
display buffers.
Any user choices entered via the switches SW1-SW4 are checked and the new
user selections are applied. May involve a change of display screen or some
parameter displayed on the LCD.
The changes are communicated to the PIC18F242 LCD controller via the SPI 2
module.
In the special case of the DTMF menu, the main routine may also kick off the DCI
module operation when the user requests DTMF tone generation.
? 2003 Microchip Technology Inc.
Advance Information
DS70099B-page 35
相关PDF资料
PDF描述
DM300016 BOARD DEMO DSPICDEM STARTER
DM300017 BOARD DEMO DSPICDEM STARTER
DM300020 BOARD DEV DSPICDEM MC1 MOTORCTRL
DM300021 MODULE PWR DSPICDEM MC1H HV 3PHS
DM300022 MODULE PWR DSPICDEM MC1L LV 3PHS
相关代理商/技术参数
参数描述
DM300015 功能描述:KIT DESIGN W/DM300014 RoHS:否 类别:编程器,开发系统 >> 过时/停产零件编号 系列:- 标准包装:1 系列:*
DM300016 功能描述:开发板和工具包 - PIC / DSPIC dsPICDEM Starter RoHS:否 制造商:Microchip Technology 产品:Starter Kits 工具用于评估:chipKIT 核心:Uno32 接口类型: 工作电源电压:
DM300017 功能描述:开发板和工具包 - PIC / DSPIC dsPICDEM 28P Starter RoHS:否 制造商:Microchip Technology 产品:Starter Kits 工具用于评估:chipKIT 核心:Uno32 接口类型: 工作电源电压:
DM300017 制造商:Microchip Technology Inc 功能描述:Microcontroller Development To
DM300018 功能描述:开发板和工具包 - PIC / DSPIC dsPICDEM 2 Demo Brd RoHS:否 制造商:Microchip Technology 产品:Starter Kits 工具用于评估:chipKIT 核心:Uno32 接口类型: 工作电源电压: