Additional Information for PIC32 CVD and CTMU Demos

Additional Information forPIC CVD and CTMU DemosAdditional Information for

PIC CVD and CTMU Demos

14 November 2011

Michael W. MannHPMD 32-Bit Application Engineer

Real-Time Debugging To assist in debugging button/slider behavior,

Microchip has provided Profilab GUI project for use on your PC

Profilab is like LabView, but much cheaperhttp://www.abacom-online.de/uk/html/profilab-expert.html

21/20/2012

Standalone Windows mTouch GUI.exe allows use of GUI without purchasing Profilab

Profilab projects can be customized to meet your debugging needs Plot average voltage and button voltage Model product front panel on a GUI tab

Additional Information

Typical Bench-Top Setup

REAL ICE Debugger

mTouchEvaluationUSB Cable

for board

31/20/2012Additional Information

PICKit Serial Analyzerinterface between PC and UART

Interface Cable

Sensor DaughterCard (8-Key)

RJ-11 to ICSP Adaptor

EvaluationBoardfor board

power

PKSA-EVB J2 Interface Cable

PKSA EVB PlugJumper Settings

Most PIC32 PIC18F


TX

Gnd

Rx

123456

2 14 36 58 710 912 1114 1316 1518 17

Footprint of J2 on EVB

PKSAPlug

EVB Plugto J2

1 x 6 x 0.1

2 x 9 x 0.1

2 14 36 58 710 912 1114 1316 1518 17

MostBoards

2 14 36 58 710 912 1114 1316 1518 17

PIC32 CTMU

2 14 36 58 710 912 1114 1316 1518 17

PIC18FCVD

Finding the .EXE GUI File

GUI .EXE

Standalone Project


GUI ProfiLabProject

Microchip Application Library Project Directory

Setting Up GUI Com Parms

Click here to launchConfiguration Window

Click to Select COM Port

61/20/2012 6Additional Information

mTouch GUI Screen 1/3Normalized Voltages for Buttons 1-4


For Matrix Keys Channels 1-3 are Columns 1-3

For Matrix Keys Channel 4 Zerod Out

mTouch GUI Screen 2/3Normalized Voltages for Buttons 5-8


For Matrix Keys Channels 5-8 are Rows1-4

mTouch GUI Screen 3/3

Prior Button Assert


Current Button Press Equivalent Slider Value

Slider value not available with Matrix Keys

Voltage Plot Screen ControlsReset Min/Max for all Channels Maximum ADC Count

Save voltageplot datato ASCII file

Save allUART datato ASCII file

Record orStop Recording

Erase fileand startover

Quit data collectionand exit GUI

Delta = Max - Min


Stop Recording over

Configuring Voltage Plots

IncreasingChannel 1 Line Width

Right mouse click in plot

window

111/20/20121/20/2012

Line Width

Plot Controls

Record StopPrintPlot

SavePlot

Copy Plotto Clipboard Delta Time between samples

Y Zoom +Zoom All

Plot Settings

121/20/20121/20/2012

Y Zoom -

X Zoom +

X Zoom -

Zoom All

Reset ZoomScroll Back in Time

Scroll Forward in Time

Profilab = LabView LiteParsing comma

delimited UART

text string

Plotting Button Voltages

Virtual Front


SavingButton

Voltagesto Text Files

Min/MaxDisplayedon Button

Voltage Plots

Front Panel on First GUI

TAB

Parsing Comma Delimited Data

Voltage Holds

Block decodes comma delimited UART string into status and voltages

Voltag

es


Holdsfor Plots

Voltag

es

Scale and Plot Channels

Virtual Front

PlotScale macro scales ADCcounts into normalized Voltage


Virtual Front Panel on First

GUI TAB

Min/MaxDisplayedon Button

Voltage Plots

Benchtop Setup for Differential with Pull-Ups Demo


Reference Signal on AN4

Channel 1 onButton Signal

100 Kohm Pull-up Resistors


Close-Up of Differential Setup using Pull-Ups

100 Kohm Pull-up Resistors

Channel 1 on


Top side of pull-ups on reference pin (AN4)


Channel 1 on Button Signal

Example Differential with Pull-Ups Scope Signals

VPOSITIVEgoes downVNEGATIVE goes up

Unasserted Asserted

Ref. Pin Voltage Button Signal

VNEGATIVEmeasurement

VPOSITIVEmeasurement

External pull-up charges button


goes up measurement

Timing of Diffl w. Pull-Ups

0

.

7

9

u

s

e

c

s

0

.

5

5

u

s

e

c

s

Interrupts MaskedInterrupts Masked

Reference Pin Voltage


V+V--

Benchtop Setup for Single-Ended or Differential w/o Pull-Ups Demos



Channel 1 on Button Signal


Example Differential w/o Pull-Ups Scope Signals

VPOSITIVE goes down VNEGATIVE goes up

Unasserted AssertedReference Signal

Button Signal

V

Multiple charge dumps fromADC SAH cap to button cap


VPOSITIVE goes down VNEGATIVE goes up

VNEGATIVEmeasurement

VPOSITIVEmeasurement

Differential w/o Pull-Ups Timings

0

.

5

8

u

s

e

c

s

1

.

0

0

u

s

e

c

s Interrupts Masked

V+ V--


Benchtop Setup for CTMU Measurements

PICKit Serial AnalyzerScope probe on Button 8

REAL ICE for debugging



on Button 8

UART TXpin on J2

Example CTMU Measurements

Reference Signal *

VPOSITIVEgoes down

Unasserted Asserted


* Reference Signal: Interrupt masking, from asm(di) to asm(ei)

InterruptsMasked

(1.53 usecs)

ADC Capture2.57 usecs

Perf. Metric: Interrupt Masking Duration

All these examples were taken usingthe Direct Key daughter card, but with different CVD/CTMU Evaluation Boards

Each application tuned to provide equivalent cap touch performance

251/20/2012

equivalent cap touch performance


Technique Vpos Vneg Vtotal

Diff w/o Pull-Ups 0.58 1 1.58

Diff w Pull-ups 0.55 0.79 1.34

CTMU 1.53 n/a 1.53

Interrupt Masking Durations [usecs]

Interrupt Masking Duration Workarounds

What if interrupts wont accommodate these black out periods? Dont use asm(di) and asm(ei) to mask

interrupts, set CapTouchMeas flag instead of asm(di), clear flag instead of asm(ei)

261/20/2012

asm(di), clear flag instead of asm(ei) ISRs set DumpMeasurement flag if ISR executes

when CapTouchMeas is set Timer ISR dumps/ignores cap touch

measurement when DumpMeasurement is set, then clears the flag


PIC32MX2xx Starter Kit App CTMU Cap Touch on 4-channel slider

Selects music Selects music volume

Three switchesI2S I/F to CODEC

271/20/2012

I2S I/F to CODEC PMP I/F to 220x172 pixel TFT display SPI I/F to microSD music card Playback of 44.1 Ksps .WAV files


PIC32MX2xx Starter Kit BoardMicroSD Memory Card

CODECHeadphone

Jack

Switch Prompts

220x172 TFT Display

PIC32MX220F032D


3 Switches

4 Channel Button/SliderSlider Display

Button Prompts

PIC32MX2xx Starter Kit Display

Button Prompts

Button State: Asserted


Switch Prompts

Slider Display

Music Timing

Selecting Music 1/2


Button State: Pressed

Selecting Music 2/2Press Switch 3

to Execute SelectionPress Switch 3

to Execute Selection


Button State: Asserted

Cap Touch Tricks 1/2 Leave interpretation of button/slider status to the main

application, only it knows context of the measurements!while(1){ // Update switches

Switch1St8 = UpdateSwitch( 1, CheckSwitch1(), (char *)0 );Switch2St8 = UpdateSwitch( 2, CheckSwitch2(), (char *)0 );Switch3St8 = UpdateSwitch( 3, CheckSwitch3(), (char *)0 );

// Update buttons/sliderif( ApplicationState != STARTUP &&

mTouchCapStatus_Check( &CurrentButtonStatus, &CurrentButtonAsserts, &Temp ) ){


{mTouchUpdated = TRUE;

if ( IgnoreSlider != TRUE ){

SliderValue = Temp;UpdateSlider( SliderValue );

}if ( IgnoreButtons != TRUE ){

UpdateButton( 1,(CurrentButtonStatus >> 0)&0x1,(CurrentButtonAsserts >> 0)&0x1,(char *)0);UpdateButton( 2,(CurrentButtonStatus >> 1)&0x1,(CurrentButtonAsserts >> 1)&0x1,(char *)0);UpdateButton( 3,(CurrentButtonStatus >> 2)&0x1,(CurrentButtonAsserts >> 2)&0x1,(char *)0);UpdateButton( 4,(CurrentButtonStatus >> 3)&0x1,(CurrentButtonAsserts >> 3)&0x1,(char *)0);

}}//end if( mTouchCheckStatus...

switch( ApplicationState ){

Cap Touch Tricks 2/2 Only update screen after completion of button scan to

prevent crosstalk between PMP screen pins and button inputs

case FILE_PLAYING_SETUP:if ( mTouchUpdated == TRUE ) // Only update display when mTouch{ // has been updated and isn't running.

UpdateSwitch(3,-1, "Pause" );UpdateSwitch(2,-1, "Stop" );UpdateSwitch(1,-1, "GoBack");


IgnoreButtons = TRUE;IgnoreSlider = FALSE;mTouchCapStatus_Reset(128);UpdateSlider(128);ApplicationState = FILE_PLAYING;

}else // mTouch is still running don't do anything{

ApplicationState = FILE_PLAYING_SETUP;}break;

case FILE_PLAYING:PMADDRSET = 1

Documents

Additional Information for PIC32 CVD and CTMU Demos