Application Note
AN_335
FT801 Graph Application
Document Reference No.:FT_001076
Version 1.0
Issue Date: 2014-07-22
This document introduces the setup of the FT801 Graph Application running on MSVC. The
objective of the Graph Application is to enable users to become familiar with the usage of the
multi-touch functionality of FT801, the design flow, and display list used to design the desired user
interface or visual effect.
Use of FTDI devices in life support and/or safety applications is entirely at the user’s risk, and the
user agrees to defend, indemnify and hold FTDI harmless from any and all damages, claims, suits
or expense resulting from such use.
Future Technology Devices International Limited (FTDI)
Unit 1, 2 Seaward Place, Glasgow G41 1HH, United Kingdom
Tel.: +44 (0) 141 429 2777 Fax: + 44 (0) 141 429 2758
Web Site: http://ftdichip.com
Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Table of Contents
1
2
Introduction ................................................................................................................ 3
1.1
Overview .............................................................................................................. 3
1.2
Scope .................................................................................................................. 3
Application Flow ........................................................................................................... 4
2.1
3
Flowchart ............................................................................................................. 4
Description .................................................................................................................. 6
3.1
Intialization .......................................................................................................... 6
3.1.1
3.2
4
Set Extended mode for multi-touch ................................................................... 6
Functionality ......................................................................................................... 7
3.2.1
Read touch control registers ............................................................................ 7
3.2.2
Draw graph .................................................................................................... 8
Contact Information ................................................................................................... 17
Appendix A– References .................................................................................................... 18
Document References .................................................................................................... 18
Acronyms and Abbreviations ........................................................................................... 18
Appendix B – List of Tables & Figures .................................................................................. 19
Appendix C– Revision History ............................................................................................. 20
2
Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
1 Introduction
This application demonstrates zoom-in and zoom-out functionality using the FT801multi-touch
capability. The application constructs a power graph on the screen. Based on user touch
movement, either-zoom in or zoom-out is performed. This application demonstrates the use of two
simultaneous touch inputs from the user.
1.1 Overview
The document will provide an understanding of the FT801 multi-touch functionality, and
demonstrate a simple use case.
1.2 Scope
This document will be used by software programmers to develop GUI applications by using the
FT801 with any MCU with a SPI master port.
For information on the project file and source code, refer to AN_264_FT_App_Gradient
Application note.
Note that detailed documentation is available on www.ftdichip.com/EVE.htm , including:
FT801 Datasheet
FT800 Series Programming Guide
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
2
Application Flow
2.1 Flowchart
4
Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Figure 2-1 Flowchart
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
3 Description
Parameters needed to be initialized are described below for constructing the display list.
3.1 Intialization
3.1.1 Set Extended mode for multi-touch
By default, the FT801 touch engine works in compatibility mode, and operates much like the
resistive touch controller in the FT800. In compatibility mode, only one touch point is detected. In
extended mode, the FT801 touch engine can detect up to 5 touch points, simultaneously.
Before entering in extended mode, user needs to do calibration in compatibility mode.
A co-processor command list is started. This command will clear the display parameters.
Ft_Gpu_CoCmd_Dlstart(phost);
Ft_App_WrCoCmd_Buffer(phost,CLEAR(1,1,1));
The following commands set the colour and then print a text message to the user which tells them
to tap on the dots during the following calibration routine. The FT800’s built-in calibration routine
is then called.
Ft_App_WrCoCmd_Buffer(phost,COLOR_RGB(255,255,255));
Ft_Gpu_CoCmd_Text(phost,FT_DispWidth/2,FT_DispHeight/2,28,OPT_CENTERX|OPT_CENTERY,"Ple
ase tap on a dot");
Ft_Gpu_CoCmd_Calibrate(phost,0);
The display list is then terminated and swapped to allow the changes to take effect.
Ft_App_WrCoCmd_Buffer(phost,DISPLAY());
Ft_Gpu_CoCmd_Swap(phost);
Ft_App_Flush_Co_Buffer(phost);
Ft_Gpu_Hal_WaitCmdfifo_empty(phost);
Figure 3-1 Calibration screen
As this application is designed to demonstrate FT801’s multi-touch functionality, set the mode to
extended. For more information please refer to the FT800 Series Programming Guide
Ft_Gpu_Hal_Wr8(phost,REG_CTOUCH_EXTENDED, CTOUCH_MODE_EXTENDED);
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
3.2 Functionality
The Graph Demo is a user interactive demo where the user can touch screen with 2 touch points
simultaneously to adjust the zoom level of the displayed image.
3.2.1 Read touch control registers
The FT801 has different touch engine and touch control registers from the FT800. These registers
provide coordinates for multiple touch points. The example code below shows the use of the
“ctouch” registers.
ft_void_t read_extended(ft_int16_t sx[5], ft_int16_t sy[5])
{
ft_uint32_t sxy0, sxyA, sxyB, sxyC;
sxy0 = Ft_Gpu_Hal_Rd32(phost,REG_CTOUCH_TOUCH0_XY);
sxyA = Ft_Gpu_Hal_Rd32(phost, REG_CTOUCH_TOUCH1_XY);
sxyB = Ft_Gpu_Hal_Rd32(phost, REG_CTOUCH_TOUCH2_XY);
sxyC = Ft_Gpu_Hal_Rd32(phost, REG_CTOUCH_TOUCH3_XY);
sx[0]
sy[0]
sx[1]
sy[1]
sx[2]
sy[2]
sx[3]
sy[3]
=
=
=
=
=
=
=
=
sxy0 >>
sxy0;
sxyA >>
sxyA;
sxyB >>
sxyB;
sxyC >>
sxyC;
16;
16;
16;
16;
sx[4] = Ft_Gpu_Hal_Rd16(phost,REG_CTOUCH_TOUCH4_X);
sy[4] = Ft_Gpu_Hal_Rd16(phost,REG_CTOUCH_TOUCH4_Y);
}
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
3.2.2 Draw graph
In this application, the FT801 graphic coprocessor command CMD_GRADIENT is used to display
the background:
Ft_Gpu_CoCmd_Gradient(phost,0, 0, 0x202020, 0, 0x11f, 0x107fff);
Figure 3-2 Gradient background
To draw the graph, the application uses the rsin function - sine with radius. It uses two values for
radius, 1200 and 700, and different theta values as shown in the code below. Using the rsin
function, values are calculated and stored in array y. VERTEX2F uses this y-value as second coordinate, and uses multiple values of SUBDIV as the first co-ordinate. The EDGE_STRIP_B
primitive and GRADIENT functions are used to draw the graph.
Ft_App_WrCoCmd_Buffer(phost,COLOR_A(255));
for (i = 0; i < (YY + 1); i++)
{
x32 = s2m(SUBDIV * i);
x2 = (ft_uint16_t)x32 + rsin(7117, x32);
y[i] = 130 * 16 + rsin(1200, (217 * x32) >> 8) + rsin(700, 3 * x2);
}
Ft_App_WrCoCmd_Buffer(phost,STENCIL_OP(INCR, INCR));
Ft_App_WrCoCmd_Buffer(phost, BEGIN(EDGE_STRIP_B));
for (j = 0; j < (YY + 1); j++)
{
Ft_App_WrCoCmd_Buffer(phost,VERTEX2F(16 * SUBDIV * j, y[j]));
}
Ft_App_WrCoCmd_Buffer(phost,STENCIL_FUNC(EQUAL, 1, 255));
Ft_App_WrCoCmd_Buffer(phost,STENCIL_OP(KEEP, KEEP));
Ft_Gpu_CoCmd_Gradient(phost,0, 0, 0xf1b608, 0, 220, 0x98473a);
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
The code above generates this initial screen:
Figure 3-3 Graph drawn using EDGE_STRIP_B
The application then uses LINE_STRIP and VERTEX2F primitives to draw the border of the graph:
Ft_App_WrCoCmd_Buffer(phost,STENCIL_FUNC(ALWAYS, 1, 255));
Ft_App_WrCoCmd_Buffer(phost, COLOR_RGB(0xE0,0xE0,0xE0));
Ft_App_WrCoCmd_Buffer(phost, LINE_WIDTH(24));
Ft_App_WrCoCmd_Buffer(phost, BEGIN(LINE_STRIP));
for (j = 0; j < (YY + 1); j++)
{
Ft_App_WrCoCmd_Buffer(phost,VERTEX2F(16 * SUBDIV * j, y[j]));
}
Figure 3-4 Graph border drawn using LINE_STRIP
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Next, the application uses LINES and VERTEX2F primitives to draw vertical lines on the
background.
Figure 3-5 Vertical lines using LINES
Now the digits are drawn with CMD_NUMBER. The following code shows the use of LINES and
VERTEX2F primitives and the CMD_NUMBER command.
Ft_App_WrCoCmd_Buffer(phost, LINE_WIDTH(max(8, pixels_per_div >> 2)));
for (m = mm[0] & ~0x3fff; m <= mm[1]; m += 0x4000)
{
x = m2s(m);
if ((-60 <= x) && (x <= 512))
{
h = 3 * (7 & (m >> 14));
Ft_App_WrCoCmd_Buffer(phost, COLOR_RGB(0,0,0));
Ft_App_WrCoCmd_Buffer(phost,COLOR_A(((h == 0) ? 192 : 64)));
Ft_App_WrCoCmd_Buffer(phost, BEGIN(LINES));
Ft_App_WrCoCmd_Buffer(phost,VERTEX2F(x*16,0));
Ft_App_WrCoCmd_Buffer(phost,VERTEX2F(x*16,272*16));
if (fadeout)
{
x -= 1;
Ft_App_WrCoCmd_Buffer(phost, COLOR_RGB(0xd0,0xd0,0xd0));
Ft_App_WrCoCmd_Buffer(phost,COLOR_A(fadeout));
Ft_Gpu_CoCmd_Number(phost,x, 0, 26, OPT_RIGHTX | 2, h);
Ft_Gpu_CoCmd_Text(phost,x, 0, 26, 0, ":00");
}
}
}
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Figure 3-6 Numbers drawn using cmd_number
Now the application uses coprocessor’s CMD_CLOCK command to draw a series of analog clocks.
clock_r = min(24, pixels_per_div >> 2);
if (clock_r > 4)
{
Ft_App_WrCoCmd_Buffer(phost,COLOR_A(200));
Ft_App_WrCoCmd_Buffer(phost, COLOR_RGB(0xff,0xff,0xff));
options = OPT_NOSECS | OPT_FLAT;
if (clock_r < 10)
options |= OPT_NOTICKS;
for (m = mm[0] & ~0x3fff; m <= mm[1]; m += 0x4000)
{
x1 = m2s(m);
h = 3 * (3 & (m >> 14));
if(x1 >= -1024)
Ft_Gpu_CoCmd_Clock(phost,x1, 270 - 24, clock_r, options, h, 0, 0, 0);
}
}
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Figure 3-7 Clocks drawn using cmd_clock
The following code is used to zoom the graph in and out, after reading touch co-ordinates.
for (i = 0; i < 2; i++)
{
if (sx[i] > -10 && !down[i])
{
down[i] = 1;
m[i] = s2m(sx[i]);
}
if (sx[i] < -10)
down[i] = 0;
}
if (down[0] && down[1])
{
if (m[0] != m[1])
set(m[0], sx[0], m[1], sx[1]);
}
else if (down[0] && !down[1])
sset(m[0], sx[0]);
else if (!down[0] && down[1])
sset(m[1], sx[1]);
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
These are the definitions of the above functions :
ft_void_t set(ft_int32_t x0, ft_int16_t y0,
ft_int32_t x1, ft_int16_t y1) {
ft_int32_t xd = x1 - x0;
ft_int16_t yd = y1 - y0;
transform_m = yd / (ft_float_t)xd;
if (transform_m < m_min)
transform_m = m_min;
transform_c = y0 - transform_m * x0;
}
ft_void_t sset(ft_int32_t x0, ft_int16_t y0)
{
transform_c = (ft_float_t)y0 - transform_m * x0;
}
ft_int16_t m2s(ft_int32_t x)
{
return (ft_int16_t)(transform_m * x + transform_c);
}
ft_int32_t s2m(ft_int16_t y)
{
return (ft_int32_t)(y - transform_c) / transform_m;
}
When the user performs a zoom-in or zoom-out, the application reads the touch co-ordinates in a
loop. These values are used for calculating the displayed image. In the set function, the difference
between x co-ordinates is calculated and according to that smallest division (i.e. transform_m and
later transform_c are calculated). These respective values are used in the remaining functions.
In the plot function, the pixel-per-division is calculated using m2s functions which are then used to
update the graph.
The sequence of screen shots below demonstrates the use of two simultaneous touch points in a
“pinching” action to zoom the graph out.
Figure 3-8 Zoom in screenshot-1
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Figure 3-9 Zoom in screenshot-2
Figure 3-10 Zoom in screenshot-3
Figure 3-11 Zoom in screenshot-4
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Figure 3-12 Zoom in screenshot-5
Figure 3-13 Zoom in screenshot-6
In a similar fashion, the next sequence of screen shots demonstrate the use of two simultaneous
touch points in an “expanding” action to zoom the graph out.
Figure 3-14 Zoom out screenshot-1
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Figure 3-15 Zoom out screenshot-2
Figure 3-16 Zoom out screenshot-3
16
Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
4 Contact Information
Head Office – Glasgow, UK
Branch Office – Tigard, Oregon, USA
Future Technology Devices International Limited
Unit 1, 2 Seaward Place, Centurion Business Park
Glasgow G41 1HH
United Kingdom
Tel: +44 (0) 141 429 2777
Fax: +44 (0) 141 429 2758
Future Technology Devices International Limited
(USA)
7130 SW Fir Loop
Tigard, OR 97223-8160
USA
Tel: +1 (503) 547 0988
Fax: +1 (503) 547 0987
E-mail (Sales)
E-mail (Support)
E-mail (General Enquiries)
[email protected]
[email protected]
[email protected]
E-Mail (Sales)
E-Mail (Support)
E-Mail (General Enquiries)
[email protected]
[email protected]
[email protected]
Branch Office – Taipei, Taiwan
Branch Office – Shanghai, China
Future Technology Devices International Limited
(Taiwan)
2F, No. 516, Sec. 1, NeiHu Road
Taipei 114
Taiwan , R.O.C.
Tel: +886 (0) 2 8791 3570
Fax: +886 (0) 2 8791 3576
Future Technology Devices International Limited
(China)
Room 1103, No. 666 West Huaihai Road,
Shanghai, 200052
China
Tel: +86 21 62351596
Fax: +86 21 62351595
E-mail (Sales)
E-mail (Support)
E-mail (General Enquiries)
E-mail (Sales)
E-mail (Support)
E-mail (General Enquiries)
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
Web Site
http://ftdichip.com
Distributor and Sales Representatives
Please visit the Sales Network page of the FTDI Web site for the contact details of our distributor(s) and sales
representative(s) in your country.
System and equipment manufacturers and designers are responsible to ensure that their systems, and any Future Technology
Devices International Ltd (FTDI) devices incorporated in their systems, meet all applicable safety, regulatory and system-level
performance requirements. All application-related information in this document (including application descriptions, suggested
FTDI devices and other materials) is provided for reference only. While FTDI has taken care to assure it is accurate, this
information is subject to customer confirmation, and FTDI disclaims all liability for system designs and for any applications
assistance provided by FTDI. Use of FTDI devices in life support and/or safety applications is entirely at the user’s risk, and the
user agrees to defend, indemnify and hold harmless FTDI from any and all damages, claims, suits or expense resulting from
such use. This document is subject to change without notice. No freedom to use patents or other intellectual property rights is
implied by the publication of this document. Neither the whole nor any part of the information contained in, or the product
described in this document, may be adapted or reproduced in any material or electronic form without the prior written consent
of the copyright holder. Future Technology Devices International Ltd, Unit 1, 2 Seaward Place, Centurion Business Park,
Glasgow G41 1HH, United Kingdom. Scotland Registered Company Number: SC136640
17
Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Appendix A– References
Document References
1. FT800 Series programmer guide
2. FT801 Embedded Video Engine Datasheet
3. Graph App
Acronyms and Abbreviations
Terms
Description
SPI
Serial Peripheral Interface
GUI
Graphical User Interface
MSVC
Microsoft Visual C
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Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Appendix B – List of Tables & Figures
Figure 2-1 Flowchart .................................................................................................. 5
Figure 3-1 Calibration screen ..................................................................................... 6
Figure 3-2 Gradient background ................................................................................. 8
Figure 3-3 Graph drawn using EDGE_STRIP_B ........................................................... 9
Figure 3-4 Graph border drawn using LINE_STRIP .................................................... 9
Figure 3-5 Vertical lines using LINES ....................................................................... 10
Figure 3-6 Numbers drawn using cmd_number ........................................................ 11
Figure 3-7 Clocks drawn using cmd_clock ................................................................ 12
Figure 3-8 Zoom in screenshot-1 ............................................................................. 13
Figure 3-9 Zoom in screenshot-2 ............................................................................. 14
Figure 3-10 Zoom in screenshot-3............................................................................ 14
Figure 3-11 Zoom in screenshot-4............................................................................ 14
Figure 3-12 Zoom in screenshot-5............................................................................ 15
Figure 3-13 Zoom in screenshot-6............................................................................ 15
Figure 3-14 Zoom out screenshot-1 ......................................................................... 15
Figure 3-15 Zoom out screenshot-2 ......................................................................... 16
Figure 3-16 Zoom out screenshot-3 ......................................................................... 16
19
Copyright © 2014 Future Technology Devices International Limited
Application Note
AN_3095 FT801 Graph Application
Version 1.0
Document Reference No.: FT_001076 Clearance No.:403
Appendix C– Revision History
Document Title:
AN_335 FT801 Graph Application
Document Reference No.:
FT_001076
Clearance No.:
FTDI#403
Product Page:
http://www.ftdichip.com/FTProducts.htm
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Revision
1.0
Changes
Initial release
Date
2014-07-22
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Copyright © 2014 Future Technology Devices International Limited