' touch display demo
' by TassyJim
' 16 Nov 2012
' see the XPT2046 or ADS7843 data sheets for a description
' of how the resistive touch screen works
cls
dim cal(4,2)
dim Mrepeat(15)

TouchX1=10 ' 4 analogue input pins for the resistors
TouchX2=8
TouchY1=9
TouchY2=7
TouchIntEnable=34 ' any digital output pin
TouchInt=28 ' digital interupt pin
Xslope=166.557
Xi=-17.196
Yslope=248.08
Yi=-268.885
sz=2
col=2
drawmode=1
setpin TouchInt, 2

gosub _menuMain
'gosub _TouchCalibrate
gosub _touchEnable
settick 100, _Touched
setpin TouchX2, 8
Pin(TouchX2)=0

_mainMenuLoop:
'do stuff while waiting for a touch
if (Xhit+Yhit) > 0 then
'XhitO=Xhit : YhitO=Yhit
if Xhit>=400 then
M=int(Yhit/43)+1
if M>6 then if Xhit>439 then M=M+4
if Mrepeat(M)=0 then
for n = 1 to 14
Mrepeat(n)=0
next n
endif
Mrepeat(M)=Mrepeat(M)+1
if Mrepeat(M)>2 then on M goto _Mu1,_Mu2,_Mu3,_Mu4,_Mu5,_Mu6,_MU7,_MU7,_MU7,_MU7,_MU7,_MU7, _MU7,_MU7
endif
on drawMode goto _Mu4,_Mu5
endif
goto _mainMenuLoop

_touchEnable:
setpin TouchY1, 1
setpin TouchY2, 1
setpin TouchX1, 1
setpin TouchX2, 8
Pin(TouchX2)=0
setpin TouchIntEnable, 8
pin(TouchIntEnable)=1
'pause 5
'setpin TouchInt, 7, _Touched
't=0
return

_Touched:
pin(0)=1
if pin(TouchInt)=0 then ' touch still there
setpin TouchIntEnable,0 ' disable the interupt resistor
gosub _readTouch
gosub _touchEnable
else
Xhit=0 ' so set the results to zero
Yhit=0
endif
font 1,1
if (Xhit+Yhit) > 0 then
print @(340,400)" "
print @(340,400)Xhit;" ";Yhit
endif
pin(0)=0
ireturn

_readTouch:
'setpin TouchInt, 0
setpin TouchY1, 1
setpin TouchY2, 1
'setpin TouchX1, 1
setpin TouchX2, 8
Pin(TouchX2)=0
setpin TouchX1, 8 '
Pin(TouchX1)=1 ' X1 is now high and X2 low
pause 1
Xvolt=pin(TouchY1) ' read the X position using Y1
'pause 3
'Xvolt=pin(TouchY1) ' read the X position again
setpin TouchX1, 1
setpin TouchX2, 1 ' set the X as input
setpin TouchY1, 8 ' and the Y as potential divider
setpin TouchY2, 8
Pin(TouchY1)=1
Pin(TouchY2)=0
pause 1
Yvolt=pin(TouchX1) ' read the Y position using X1
'pause 3
'Yvolt=pin(TouchX1) ' read the Y position again
Xhit=int(Xi + Xvolt*Xslope) 'int(mm.hres*Xvolt/3.3) ' you can scale to any value here
Yhit=int(Yi + Yvolt*Yslope) 'int(mm.vres*Yvolt/3.3)
if Xhit >500 or Yhit < -15 then 'reading is suspect
Xhit=0 ' so set the results to zero
Yhit=0
endif
return

_TouchCalibrate:
circle (10,10),4,6,F
gosub _touchEnable
while t=0
wend
cal(1,1)=Xvolt
cal(1,2)=Yvolt
circle (470,10),4,6,F
pause 1000
gosub _touchEnable
while t=0
wend
cal(2,1)=Xvolt
cal(2,2)=Yvolt
circle (10,420),4,6,F
pause 1000
gosub _touchEnable
while t=0
wend
cal(3,1)=Xvolt
cal(3,2)=Yvolt
circle (470,420),4,6,F
pause 1000
gosub _touchEnable
while t=0
wend
cal(4,1)=Xvolt
cal(4,2)=Yvolt
cal(1,1)=(cal(1,1)+cal(3,1))/2
cal(1,2)=(cal(1,2)+cal(2,2))/2
cal(2,1)=(cal(2,1)+cal(4,1))/2
cal(2,2)=(cal(3,2)+cal(4,2))/2
Xslope=460/(cal(2,1)-cal(1,1))
Xi=10 - cal(1,1)*Xslope
Yslope=410/(cal(2,2)-cal(1,2))
Yi=10 - cal(1,2)*Yslope
print Xslope;" ";Xi
print Yslope;" ";Yi
return

_menuMain:
gosub _drawMenuBox
font 1, 2
print @(405,1*43-25)"New"
print @(405,2*43-25)"Load"
print @(405,3*43-25)"Save"
print @(405,4*43-25)"Free"
print @(405,5*43-25)"Line"
print @(405,6*43-25)"Size"
for n = 7 to 10
line (401,(n-1)*43+1) - (439,n*43),n-7, BF
line (441,(n-1)*43+1) - (479,n*43),n-3, BF
next n
line (440,301) - (440,430),6
return

_drawMenuBox:
for n = 1 to 10
line (400,(n-1)*43) - (479,n*43),6, B
next n
return

_Mu1: ' new
pause 120
if Xhit>400 and Yhit<43 then
line (1,1) - (399,431),0,BF
gosub _menuMain
endif
goto _mainMenuLoop

_Mu2: ' load

goto _mainMenuLoop

_Mu3: ' save
savebmp "sketch.bmp"
goto _mainMenuLoop

_Mu4: 'freehand
drawMode=1
if Xhit+Yhit >0 then
if Xhit >=400 then goto _mainMenuLoop
circle (Xhit,Yhit),sz,col,F
endif
goto _Mu4

_Mu5: ' line
drawMode=2
goto _mainMenuLoop

_Mu6: ' size
if Xhit>440 then
sz=sz+1
if Sz=5 then sz=4
else
sz=sz-1
if sz=0 then sz=1
endif
goto _mainMenuLoop

_Mu7: ' size
col=M-7
print @(340,420)M;" "
goto _mainMenuLoop