Help Make Sense of QT510 SPI Protocol

[bbarney]

the only thing I've found is this site
http://www.tigoe.net/pcomp/code/arch...o/000331.shtml

[GCollier]

Well I've been tinkering a bit more. I did a new board layout on some thinner material. I'm using a 5V regulator instead of a 3.3V one so that my levels are the same between the pic and the sensor IC. Still, I cant seem to get DRDY to go high...but if I force it data transmits just fine. I've attached my code below, it could use a bit of improvement but it works with a PIC16F88

'************************************************* ***************
'* Name : QT510.BAS *
'* Author : George Collier *
'* Notice : Copyright (c) 2006 *
'* : All Rights Reserved *
'* Date : 01/13/2006 *
'* Version : 1.0 *
'* Notes : QTouch 510 Interface Test *
'* : *
'************************************************* ***************
@ DEVICE WDT_OFF, MCLR_OFF
@_INTRC_OSC_NOCLKOUT ' Set to internal osc
DEFINE OSC 8
DEFINE LCD_DREG PORTA
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTA
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 3
DEFINE LCD_COMMANDUS 2000
DEFINE SHIFT_PAUSEUS 1000

'added for the 16F88
'OSCCON = %01100000 ' set internal osc to 4 MHZ
OSCCON = %01110000 ' set internal osc to 8 MHZ
CMCON = 7 ' shut off comparators
ADCON1 = 7 ' PORTA digital
TRISA = %11000000 ' Set PORTA to all outputs, A6 and A7 Input
TRISB = %00000000 ' Set PORTB to all outputs
'@_INTRC_OSC_NOCLKOUT ' Set to internal osc
'end add for 16F88
ANSEL = 0 'set all ports digital

I CON 254 ' Control Byte
CLR CON 1 ' Clear the display
LINE_1 CON 128 ' Point LCD to beginning of line 1
LINE_2 CON 192 ' Point LCD to beginning of line 2
LINE_3 CON 148 ' Point LCD to beginning of line 3
LINE_4 CON 212 ' Point LCD to beginning of line 4
CGRAM CON 64 ' Point to Cgram within LCD
SHIFT_L CON 24 ' Shift LCD display left
SHIFT_R CON 28 ' Shift LCD display right

SDO var PORTB.1 : LOW SDO ' PIC Data out pin
SDI VAR PORTA.6 : LOW SDI ' PIC Data in pin
SCLK var PORTB.6 : high SCLK ' PIC Clock out pin
qtSS var PORTB.7 : HIGH qtSS ' QTouch Slave Select Pin
DRDY VAR PORTA.7 : LOW DRDY ' QTouch DRDY Pin (INPUT)
'INPUT PORTA.7 'set DRDY pin to input

QT_POSN VAR Byte : QT_POSN = %01000000 ' Stores QTouch Position Data
QT_CFG_NULL VAR BYTE : QT_CFG_NULL = %00000000 'QTouch Null Command
QT_CFG_PROX VAR BYTE : QT_CFG_PROX = %01001010 'Qtouch Proximity Sensitivity
QT_CFG_TOUCH VAR BYTE : QT_CFG_TOUCH = %10001010 'Qtouch Touch Sensitivity
QT_CFG_DRIFT VAR BYTE : QT_CFG_DRIFT = %00000011 'Qtouch Drift Compensate
QT_CFG_CAL VAR BYTE : QT_CFG_CAL = %00000001 'Qtouch Calibration Command
READS VAR BYTE : READS = 0 'Counter for periodic drift compensation
STAT VAR QT_POSN.7 'QTouch STATUS

Pause 2000 ' Wait for LCD to startup

Lcdout $fe, 1 'Clear the LCD
LCDOUT " QWheel Test "
GOSUB INITIALIZE
PAUSE 2000
LCDOUT I, CLR
LCDOUT I, LINE_2, "READY FOR DATA"
GOTO LOOP

INITIALIZE:
IF DRDY = 1 THEN 'check if QTouch ready for data
PAUSEUS 13
Low QTSS 'Ready the QTouch to receive Data
SHIFTOUT SDO, SCLK, 5, [QT_CFG_PROX] 'Configure Proximity Sensitivity
HIGH qtss
PAUSEUS 100
LOW QTSS
PAUSEUS 13
SHIFTOUT SDO, SCLK, 5, [QT_CFG_TOUCH] 'Configure Touch Sensitivity
HIGH qtSS
PAUSEUS 100
LOW QTSS
PAUSEUS 13
SHIFTOUT SDO, SCLK, 5, [QT_CFG_NULL] 'Send NULL Command
HIGH qtSS 'Close the connection
pause 500
LCDOUT I, LINE_2, "INITIALIZE COMPLETE"
ENDIF
RETURN

LOOP:
if DRDY = 1 THEN GOSUB READ_QT
GOSUB QT_LCD
PAUSE 500
GOTO Loop

CALIBRATE:
PAUSEUS 13
LOW qtSS
SHIFTOUT SDO, SCLK, 5, [QT_CFG_CAL\8] 'send the recalibrate command
HIGH QTSS
RETURN

QT_LCD:
SELECT CASE STAT 'determine touch status and output data

CASE 1 'board is touched
LCDOUT I, CLR
LCDOUT "TOUCHED"
QT_POSN = QT_POSN / 2 'strips the position bit from QT_POSN
LCDOUT I, LINE_2, "POSITION: ", DEC QT_POSN 'prints position 0-127 on LCD
PAUSE 100
CASE 0 'board is not touched
LCDOUT I, CLR
LCDOUT I, LINE_1, "NOT TOUCHED"
LCDOUT I, LINE_2, "NO POSITION"
'if (QT_POSN.1 = 1) and (DRDY = 1) then GOSUB CALIBRATE 'recalibrate on error flag
' LCDOUT I, LINE_2, "RECALIBRATED"
' Pause 1000
END SELECT
RETURN

READ_QT:
LOW SDO 'Send all 0 on SHIFTIN = Null Command
LOW qtSS 'Activate QTouch
PAUSEUS 13
SHIFTIN SDI, SCLK, 6,[QT_POSN\8] 'read position data to QT_POSN
HIGH qtSS 'Deactivate QTouch
STAT = QT_POSN.7 'get the touch status from the output 0 = not touched
READS = READS + 1 'increment reads counter for drift compensation
if (READS > 10) and (STAT = 0) then 'drift compensate every 10 reads if no touch
LOW SDO
LOW qtSS 'Activate QTouch
PAUSEUS 13
SHIFTOUT SDO, SCLK, 5, [QT_CFG_DRIFT] 'Drift Compensate
HIGH qtSS
PAUSEUS 20
READS = 0 'reset the reads counter
ENDIF
RETURN

END