Arbitrary Waveform Generator Using DAC and DMAww1.microchip.com/downloads/en/Appnotes/00003312A.pdf · 2019. 12. 18. · This application note describes how an Arbitrary Waveform

AN3312 Arbitrary Waveform Generator Using DAC and DMA

Introduction

Author: Alec Miller, Microchip Technology Inc.

This application note describes how an Arbitrary Waveform Generator (AWG) can be implemented using DirectMemory Access (DMA) and an 8-bit buffered Digital-to-Analog Converter (DAC). The waveform that is generated inthis application can be up to 255 samples long, and is created using a look-up table (LUT) in RAM with data fromuser-generated files loaded onto an SD card. Once the waveform has been read from the SD card, the AWGoperates core independently without additional CPU intervention. The waveforms are generated by using a DMA toautomatically load values from the LUT in RAM into the DAC output register at an interval determined by a timer.

© 2019 Microchip Technology Inc. Application Note DS00003312A-page 1

Table of Contents

Introduction.....................................................................................................................................................1

1. Theory of Operation................................................................................................................................ 3

1.1. Waveform Generation.................................................................................................................. 31.2. DAC..............................................................................................................................................31.3. DMA............................................................................................................................................. 3

2. Implementation........................................................................................................................................4

2.1. DAC..............................................................................................................................................42.2. DMA............................................................................................................................................. 42.3. Timer............................................................................................................................................ 52.4. File System...................................................................................................................................52.5. Hardware......................................................................................................................................52.6. User Interface...............................................................................................................................6

3. Results.................................................................................................................................................... 7

4. Appendix................................................................................................................................................. 8

The Microchip Website.................................................................................................................................10

Product Change Notification Service............................................................................................................10

Customer Support........................................................................................................................................ 10

Microchip Devices Code Protection Feature................................................................................................ 10

Legal Notice................................................................................................................................................. 10

Trademarks...................................................................................................................................................11

Quality Management System....................................................................................................................... 11

Worldwide Sales and Service.......................................................................................................................12

AN3312


1. Theory of Operation

1.1 Waveform GenerationArbitrary waveform generators are systems capable of generating an analog waveform and can take any form. Theyare often used as test equipment to test the response of a circuit to a particular input. The signal is generated bycontinuously adjusting the output of a Digital-to-Analog Converter (DAC) to create an analog signal made of a seriesof discrete steps. The values can either be generated programmatically in real time, or loaded from a look-up table.

The limitations of an Arbitrary Waveform Generator are the input voltage range, the characteristics of the DAC usedto create the signal, and the performance characteristics of the device feeding data to the DAC. The quality of thegenerated waveform is directly related to the sample rate and resolution of the DAC module being used.

1.2 DACThe Digital-to-Analog Converter (DAC) can be used to convert digital input values to an analog output. The DAC usesa reference voltage and outputs a corresponding fraction of that voltage, which is determined by the value loaded intothe DACxDAT register.

The resolution of a DAC is determined by the number of bits in the input code and can be calculated using thefollowing formula:�� = ��2��.��− 1This application uses the 8-bit DAC on the PIC18F47Q43, which at 5V, gives a resolution of 20 mV. The output of aDAC with a given input code is typically defined using the following formula:�� = ��2��.��− 1 ⋅ ��

1.3 DMADirect Memory Access (DMA) is a subsystem that can transfer data between different memory regions, includingregister memory, without CPU intervention. This feature allows data to be transferred between peripherals with amuch lower CPU overhead in comparison to transferring the data without DMA. DMA can be beneficial in applicationsthat require data to be transferred at rates close to the clock frequency of the device, such as in this ArbitraryWaveform Generator application.

The DMA module is comprised of a DMA controller and multiple interface channels that allows data transfer betweenthe device memory regions. The System Arbiter is used to allocate priority levels for different system events, and canbe used to give a DMA higher priority than main code execution or even ISR execution. The DMA subsystemoperates on an independent data and address bus which allows data to be transferred with no impact on CPUoperation (assuming the DMA has been configured to have a lower priority than the CPU using the System Arbiter).

The transfer process can be configured to be triggered by various system events. For instance, a DMA can beconfigured to automatically transfer a message received by a UART to a user-defined storage buffer when the UARTreceive interrupt is triggered.

Each DMA channel has its own configurable priority level, which can be set using the System Arbiter. By default,DMA has lower priority than the CPU lowest priority and will only execute during holes in CPU execution due to two-cycle instructions, such as GOTO. The DMA can be configured to pause CPU execution when triggered, or to evenpause interrupt execution, depending on the priority set using the System Arbiter.

AN3312Theory of Operation


2. Implementation

2.1 DACIn this application, the DAC is configured to use VDD as the positive reference and ground as the negative reference.To allow for smooth waveforms with desired amplitudes below VDD, the Fixed Voltage Reference (FVR) can supplythe positive reference, or a second DAC could supply VREF to allow for greater flexibility, although this would requirean external DAC in cases where the device has only a single DAC.

2.2 DMAThis application uses two DMA modules, as shown in Figure 2-1. One DMA module feeds data from the look-up table(LUT) into the DAC, and the other DMA feeds the Analog-to-Digital Converter (ADC) reading from a potentiometer tothe period value of the Timer2 module, which determines the frequency of the waveform.Figure 2-1. AWG Block Diagram

DACDMA1LUT

TMR2DMA2T2PR

ADCADRESH

Conv. Complete

POT

OUT

The DAC feeder (DMA1) is configured to be triggered by the Timer2 output. The source address and length are userselectable and the destination is DAC1DAT. The period selector (DMA2) is configured to be triggered by theconversion complete flag of the continuously converting ADC, which is continuously sampling a potentiometer. Thesource is the upper byte of the left-justified output, and the destination is the Timer2 period value.

Example 2-1. Set DMA Source

void dma_setSource(uint8_t dma, void * source, uint16_t length){ DMASELECT = dma; DMAnCON0bits.EN = 0; DMAnSSA = source; DMAnSSZH = (length >> 8) & 0xFF; DMAnSSZL = length & 0xFF; DMAnCON0bits.EN = 1;}

Example 2-2. DMA1 - Look-Up Table to Data Transfer

DMASELECT = 0;DMAnCON1bits.DMODE = 0b00; // Destination pointer unchangedDMAnCON1bits.SMODE = 0b01; // Increment source pointerDMAnDSA = &DAC1DATL;DMAnDSZL = 1; // Destination size 1DMAnSIRQ = 0x1B; // TMR2 triggerDMAnCON0bits.SIRQEN = 1; // Allow hardware to trigger start

AN3312Implementation


Example 2-3. DMA1 - ADC to TMR2 Data Transfer

DMASELECT = 1;DMAnDSA = &T2PR; // Destination TMR0HDMAnDSZL = 1; // Destination size 1DMAnSSZH = 0;DMAnSSZL = 1; // Source size 1DMAnSSA = &ADRESH; // Source ADCDMAnSIRQ = 0xA; // ADC ConversionDMAnCON0bits.SIRQEN = 1; // Allow hardware to trigger startDMAnCON0bits.EN = 1;

2.3 TimerIn this application, the Timer2 module is configured with a prescaler of 1:8 and a source of FOSC/4, meaning thatwhen the period value is set to zero, a new value will be loaded every 32 clock cycles or eight instruction cycles. Thisaction requires a hole in the form of a branch or GOTO at least once every eight words. Since the timer value will onlybe updated when a hole occurs, there is an increased risk that an update will be missed if no hole occurs beforeanother transfer is triggered. Depending on the importance of uninterrupted execution of the main application versusthe importance of waveform output quality, the System Arbiter can be used to adjust the priorities to give the DMAbeing used as the DAC feeder a higher priority than the main execution. Another option would be to cut the frequencyin half and either limit the maximum frequency of the output or cut the number of sample points in half.

2.4 File SystemThe SD card file system used is based on a standard FAT file system, which can be loaded normally by a PC. Eachwaveform is comprised of its own file, with the file names consisting of sequential numbers starting at ‘0’. Thecontents of the file consist of a 16-character description (e.g., “Sawtooth”) that is buffered with spaces as needed, aone-byte length field indicating the length of the waveform and up to 255 single-byte samples of the waveform to begenerated.

The waveforms on the SD card are generated using a Python script that converts standard single-channel signed 16-bit pulse code modulation (PCM) .WAV files to an 8-bit unsigned PCM with the meta data, as described above.The .WAV files that the Python script converts from can be created using standard audio editing software. The Pythonscript also down-samples the audio waveform to the desired number of samples.

On start-up, the PIC® device reads the contents of the SD card to determine the number of waveforms saved on theSD card. The descriptions of each file are then stored in RAM to prevent the need to repeatedly read from the SDcard while cycling through choices.

When a waveform is loaded, the contents of the data portion of the file are read into the look-up table addressed bythe DMA, and the length field is used to control the length of data read by the DMA.

2.5 HardwareThis application was created using the Curiosity High Pin Count (HPC) Development Board with a PIC18F47Q43microcontroller. The MikroElektronika microSD Click board™ and the LCD mini Click board™ were used for SD cardreading and the display, respectively. The microSD Click board is a standard SD card connector that can beinterfaced using the SPI protocol. The LCD Click board consists of a 2x16 HD44780-compatible LCD display in 4-data-pin mode, connected to a MCP23S17 port expander and MCP4161 digital potentiometer for contrast control(both controlled using SPI). The ADC continuously samples the potentiometer on pin RA0 to control the frequency ofthe waveform being generated. The buttons on pins RB4 and RC5 are used to select the waveform that will begenerated, as described in the User Interface section, and the waveform is on pin RA2.



2.6 User InterfaceThis application implements a very simple user interface that is used to control the AWG. The button on pin RC5cycles between the different waveforms saved to the SD card, displaying the 16-character descriptor on the bottomline of the LCD screen. If the selected file is already loaded, the top line displays the text “Current file,” otherwise itwill display “Select file”. The button on pin RB4 loads the selected waveform into the DMA look-up table and sets theDMA scan length to the length of the sample.



3. ResultsThe waveform generator was able to create the triangular and sinusoidal waveforms shown in Figure 3-1 and Figure3-2, respectively, with an adjustable frequency. With a clock speed of 64 MHz, an effective prescaler of 1:32 (1:8prescaler and FOSC/4 source) and that there were 100 samples in the look-up tables, the maximum frequency of thewaveform is 20 kHz. Depending on the needs of the application, this frequency could be increased, either at theexpense of the signal quality by reducing the number of samples, or at the expense of other program execution byprioritizing the DMA over CPU execution to allow for a faster sample rate.

Figure 3-1. Sinusoidal Output

Figure 3-2. Triangular Output

AN3312Results


4. AppendixFigure 4-1. Main Schematic

1

1

2

2

3

3

4

4

D D

C C

B B

A A

Title

Number RevisionSize

A

Date: 2019-09-12 Sheet ofFile: Main.SchDoc Drawn By:

RA02

RA13

RA24

RA35

RA46

RA57

RA614

RA713

RB033

RB134

RB235

RB336

RB437

RB538

RB6/ICSPCLK39

RB7/ICSPDAT40

RC0 15

RC1 16

RC2 17

RC3 18

RC4 23

RC5 24

RC6 25

RC7 26

RD0 19

RD1 20

RD2 21

RD3 22

RD4 27

RD5 28

RD6 29

RD7 30

RE08

RE19

RE210

VDD

11

VDD

32

VSS

12

VSS

31

RE3/MCLR/VPP10

U1PIC18F47Q43

123456

J1

PICkit

GND GND

VCC VCC

SCLKMISOMOSI

MCLR

ICSPDAT/DACICSPCLK

MCLR

ICSPDAT/DACICSPCLK

1 2S2

10K

R6

VCC

GND

1KR5

1KR2

10K R1

VCC

1 2S1

GND

C20.1µF

C40.1µF

C11μF

C31μF

VCC VCC VCC VCC

GND GND GND GND

GND

VCC

R31K

R4

VCC

GND

POT_CSCS_SD

EXP_nRSTLCD_CS

11

22

J2

GND

11 22

J3VCC

GND

A Miller

Main

1 2

1

AN3312Appendix


Figure 4-2. SPI Schematic

1

1

2

2

3

3

4

4

D D

C C

B B

A A

Title

Number RevisionSize

A

Date: 2019-09-12 Sheet ofFile: SPI.SchDoc Drawn By:

GPB0 1

GPB1 2

GPB2 3

GPB3 4

GPB4 5

GPB5 6

GPB6 7

GPB7 8VDD9

VSS10

CS11

SCK12

SI13

SO14

A015

A116

A217

RESET18

INTB19INTA20

GPA021

GPA122

GPA223

GPA324

GPA425

GPA5 26

GPA6 27

GPA7 28

U2

MCP23S17

VSS1VCC2VEE3RS4R/W5E6DB07DB18DB29DB310DB411DB512DB613DB7

14 LED(+)15 LED(-)16

J5

16 x 2 HD44780

RS

RS

GND

VCC

EDB4DB5DB6DB7

E

DB4DB5DB6DB7

SDI/SDO3

VSS 4

CS1 P0A 5

SCK2

VDD8

P0W 6

P0B 7

U3

MCP4161

VEE

VEE

GND

VCC

POT_CSSCLK

MOSI

MISOMOSISCLK

EXP_CS

EXP_nRST

GND

SCLKMOSIMISOEXP_CSPOT_CS

EXP_nRST

SCLKMOSIMISO

EXP_CSPOT_CS

EXP_nRST

VCC

VCC

C60.1µF

C70.1µF

GND GND

VCC VCC

10K

R910K

R8

VCC VCC

EXP_CSPOT_CS

NC1

CS2

DI3

vdd4

SCLK5

Vss6

DO7

NC8

sw 19

sw 210

Molex 503182-1853

mic

roSD

J4

MISO

SCLK

MOSISD_CS

10K

R7

VCC

SD_CS

SD_CS SD_CS

GND

VCC

C50.1µF

GND

VCC

A Miller

SPI Devices

2 2

1

AN3312Appendix


The Microchip WebsiteMicrochip provides online support via our website at http://www.microchip.com/. This website is used to make filesand information easily available to customers. Some of the content available includes:

• Product Support – Data sheets and errata, application notes and sample programs, design resources, user’sguides and hardware support documents, latest software releases and archived software

• General Technical Support – Frequently Asked Questions (FAQs), technical support requests, onlinediscussion groups, Microchip design partner program member listing

• Business of Microchip – Product selector and ordering guides, latest Microchip press releases, listing ofseminars and events, listings of Microchip sales offices, distributors and factory representatives

Product Change Notification ServiceMicrochip’s product change notification service helps keep customers current on Microchip products. Subscribers willreceive email notification whenever there are changes, updates, revisions or errata related to a specified productfamily or development tool of interest.

To register, go to http://www.microchip.com/pcn and follow the registration instructions.

Customer SupportUsers of Microchip products can receive assistance through several channels:

• Distributor or Representative• Local Sales Office• Embedded Solutions Engineer (ESE)• Technical Support

Customers should contact their distributor, representative or ESE for support. Local sales offices are also available tohelp customers. A listing of sales offices and locations is included in this document.

Technical support is available through the website at: http://www.microchip.com/support

Microchip Devices Code Protection FeatureNote the following details of the code protection feature on Microchip devices:

• Microchip products meet the specification contained in their particular Microchip Data Sheet.• Microchip believes that its family of products is one of the most secure families of its kind on the market today,

when used in the intended manner and under normal conditions.• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these

methods, to our knowledge, require using the Microchip products in a manner outside the operatingspecifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft ofintellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code

protection does not mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protectionfeatures of our products. Attempts to break Microchip’s code protection feature may be a violation of the DigitalMillennium Copyright Act. If such acts allow unauthorized access to your software or other copyrighted work, youmay have a right to sue for relief under that Act.

Legal NoticeInformation contained in this publication regarding device applications and the like is provided only for yourconvenience and may be superseded by updates. It is your responsibility to ensure that your application meets with

AN3312


http://www.microchip.com/http://www.microchip.com/pcnhttp://www.microchip.com/support

your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHEREXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION,INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY ORFITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchipdevices in life support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend,indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from suchuse. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights unlessotherwise stated.

TrademarksThe Microchip name and logo, the Microchip logo, Adaptec, AnyRate, AVR, AVR logo, AVR Freaks, BesTime,BitCloud, chipKIT, chipKIT logo, CryptoMemory, CryptoRF, dsPIC, FlashFlex, flexPWR, HELDO, IGLOO, JukeBlox,KeeLoq, Kleer, LANCheck, LinkMD, maXStylus, maXTouch, MediaLB, megaAVR, Microsemi, Microsemi logo, MOST,MOST logo, MPLAB, OptoLyzer, PackeTime, PIC, picoPower, PICSTART, PIC32 logo, PolarFire, Prochip Designer,QTouch, SAM-BA, SenGenuity, SpyNIC, SST, SST Logo, SuperFlash, Symmetricom, SyncServer, Tachyon,TempTrackr, TimeSource, tinyAVR, UNI/O, Vectron, and XMEGA are registered trademarks of Microchip TechnologyIncorporated in the U.S.A. and other countries.

APT, ClockWorks, The Embedded Control Solutions Company, EtherSynch, FlashTec, Hyper Speed Control,HyperLight Load, IntelliMOS, Libero, motorBench, mTouch, Powermite 3, Precision Edge, ProASIC, ProASIC Plus,ProASIC Plus logo, Quiet-Wire, SmartFusion, SyncWorld, Temux, TimeCesium, TimeHub, TimePictra, TimeProvider,Vite, WinPath, and ZL are registered trademarks of Microchip Technology Incorporated in the U.S.A.

Adjacent Key Suppression, AKS, Analog-for-the-Digital Age, Any Capacitor, AnyIn, AnyOut, BlueSky, BodyCom,CodeGuard, CryptoAuthentication, CryptoAutomotive, CryptoCompanion, CryptoController, dsPICDEM,dsPICDEM.net, Dynamic Average Matching, DAM, ECAN, EtherGREEN, In-Circuit Serial Programming, ICSP,INICnet, Inter-Chip Connectivity, JitterBlocker, KleerNet, KleerNet logo, memBrain, Mindi, MiWi, MPASM, MPF,MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM,PICDEM.net, PICkit, PICtail, PowerSmart, PureSilicon, QMatrix, REAL ICE, Ripple Blocker, SAM-ICE, Serial QuadI/O, SMART-I.S., SQI, SuperSwitcher, SuperSwitcher II, Total Endurance, TSHARC, USBCheck, VariSense,ViewSpan, WiperLock, Wireless DNA, and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A.and other countries.

SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.

The Adaptec logo, Frequency on Demand, Silicon Storage Technology, and Symmcom are registered trademarks ofMicrochip Technology Inc. in other countries.

GestIC is a registered trademark of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of MicrochipTechnology Inc., in other countries.

All other trademarks mentioned herein are property of their respective companies.© 2019, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.

ISBN: 978-1-5224-5423-6

Quality Management SystemFor information regarding Microchip’s Quality Management Systems, please visit http://www.microchip.com/quality.

AN3312


http://www.microchip.com/quality

AMERICAS ASIA/PACIFIC ASIA/PACIFIC EUROPECorporate Office2355 West Chandler Blvd.Chandler, AZ 85224-6199Tel: 480-792-7200Fax: 480-792-7277Technical Support:http://www.microchip.com/supportWeb Address:http://www.microchip.comAtlantaDuluth, GATel: 678-957-9614Fax: 678-957-1455Austin, TXTel: 512-257-3370BostonWestborough, MATel: 774-760-0087Fax: 774-760-0088ChicagoItasca, ILTel: 630-285-0071Fax: 630-285-0075DallasAddison, TXTel: 972-818-7423Fax: 972-818-2924DetroitNovi, MITel: 248-848-4000Houston, TXTel: 281-894-5983IndianapolisNoblesville, INTel: 317-773-8323Fax: 317-773-5453Tel: 317-536-2380Los AngelesMission Viejo, CATel: 949-462-9523Fax: 949-462-9608Tel: 951-273-7800Raleigh, NCTel: 919-844-7510New York, NYTel: 631-435-6000San Jose, CATel: 408-735-9110Tel: 408-436-4270Canada - TorontoTel: 905-695-1980Fax: 905-695-2078

Australia - SydneyTel: 61-2-9868-6733China - BeijingTel: 86-10-8569-7000China - ChengduTel: 86-28-8665-5511China - ChongqingTel: 86-23-8980-9588China - DongguanTel: 86-769-8702-9880China - GuangzhouTel: 86-20-8755-8029China - HangzhouTel: 86-571-8792-8115China - Hong Kong SARTel: 852-2943-5100China - NanjingTel: 86-25-8473-2460China - QingdaoTel: 86-532-8502-7355China - ShanghaiTel: 86-21-3326-8000China - ShenyangTel: 86-24-2334-2829China - ShenzhenTel: 86-755-8864-2200China - SuzhouTel: 86-186-6233-1526China - WuhanTel: 86-27-5980-5300China - XianTel: 86-29-8833-7252China - XiamenTel: 86-592-2388138China - ZhuhaiTel: 86-756-3210040

India - BangaloreTel: 91-80-3090-4444India - New DelhiTel: 91-11-4160-8631India - PuneTel: 91-20-4121-0141Japan - OsakaTel: 81-6-6152-7160Japan - TokyoTel: 81-3-6880- 3770Korea - DaeguTel: 82-53-744-4301Korea - SeoulTel: 82-2-554-7200Malaysia - Kuala LumpurTel: 60-3-7651-7906Malaysia - PenangTel: 60-4-227-8870Philippines - ManilaTel: 63-2-634-9065SingaporeTel: 65-6334-8870Taiwan - Hsin ChuTel: 886-3-577-8366Taiwan - KaohsiungTel: 886-7-213-7830Taiwan - TaipeiTel: 886-2-2508-8600Thailand - BangkokTel: 66-2-694-1351Vietnam - Ho Chi MinhTel: 84-28-5448-2100

Austria - WelsTel: 43-7242-2244-39Fax: 43-7242-2244-393Denmark - CopenhagenTel: 45-4450-2828Fax: 45-4485-2829Finland - EspooTel: 358-9-4520-820France - ParisTel: 33-1-69-53-63-20Fax: 33-1-69-30-90-79Germany - GarchingTel: 49-8931-9700Germany - HaanTel: 49-2129-3766400Germany - HeilbronnTel: 49-7131-72400Germany - KarlsruheTel: 49-721-625370Germany - MunichTel: 49-89-627-144-0Fax: 49-89-627-144-44Germany - RosenheimTel: 49-8031-354-560Israel - Ra’ananaTel: 972-9-744-7705Italy - MilanTel: 39-0331-742611Fax: 39-0331-466781Italy - PadovaTel: 39-049-7625286Netherlands - DrunenTel: 31-416-690399Fax: 31-416-690340Norway - TrondheimTel: 47-72884388Poland - WarsawTel: 48-22-3325737Romania - BucharestTel: 40-21-407-87-50Spain - MadridTel: 34-91-708-08-90Fax: 34-91-708-08-91Sweden - GothenbergTel: 46-31-704-60-40Sweden - StockholmTel: 46-8-5090-4654UK - WokinghamTel: 44-118-921-5800Fax: 44-118-921-5820

Worldwide Sales and Service


http://www.microchip.com/supporthttp://www.microchip.com

IntroductionTable of Contents1. Theory of Operation1.1. Waveform Generation1.2. DAC1.3. DMA

2. Implementation2.1. DAC2.2. DMA2.3. Timer2.4. File System2.5. Hardware2.6. User Interface

3. Results4. AppendixThe Microchip WebsiteProduct Change Notification ServiceCustomer SupportMicrochip Devices Code Protection FeatureLegal NoticeTrademarksQuality Management SystemWorldwide Sales and Service

Documents

Arbitrary Waveform Generator Using DAC and DMAww1.microchip.com/downloads/en/Appnotes/00003312A.pdf · 2019. 12. 18. · This application note describes how an Arbitrary Waveform