Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Issue Date: 2013-09-09 This application note illustrates how to develop a GPS to USB design using the FTDI FT230X chip. 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 © 2012 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 Table of Contents 1 Introduction .................................................................................................................................... 2 1.1 Overview ................................................................................................................................. 2 1.2 Background ............................................................................................................................. 2 2 Example Circuit ............................................................................................................................... 3 3 PCB Data.......................................................................................................................................... 6 4 Using FT230XQ GPS Dongle as a location sensor under Windows 7 .............................................. 7 5 Contact Information........................................................................................................................ 9 Appendix A – References ...................................................................................................................... 10 Document References....................................................................................................................... 10 Acronyms and Abbreviations ............................................................................................................ 10 Appendix B – List of Figures .................................................................................................................. 11 List of Figures .................................................................................................................................... 11 Appendix C – Revision History .............................................................................................................. 12 1 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 1 Introduction The FT230X is a USB to serial UART interface with optimised pin count for smaller PCB designs, offering single-chip USB to asynchronous serial data transfer interface. The entire USB protocol is handled on the chip. No USB specific firmware programming is required. Small PCB footprint makes it ideal for space constrained applications such as the design of a GPS dongle – as described in this application note. 1.1 Overview This application note gives detail of how to implement a GPS dongle design, which can be used to enable location services under Windows Operating System, using the FT230X USB to basic UART Bridge IC. The application can be used as a reference design for the FT230X and details of the schematic and layout are given for reference. 1.2 Background Computers today are more mobile than ever. From small laptops to Tablet PCs, many computers can go wherever the user wants to go. Programs that take advantage of the computer's mobility can add significant value to people's lives. For example, a program that can find nearby restaurants and provide driving directions would seem to be a natural fit for a portable computer. Starting with Windows 7, the Windows Sensor and Location platform enables the computer and applications to adapt to their current environment. With location sensors – such as GPS devices, applications and gadgets can know exactly where they are, enabling them to provide relevant content and functionality. 2 Copyright © 2013 Future Technology Devices International Limited USB Plug VBUS DD+ GND CN1 1 2 3 4 GND C3 10nF GND C5 0.1uF 2x47pF C1 C2 FB1 600R/0.5A GND C4 4.7uF R1 R2 27R 27R 9 7 6 8 GND C6 0.1uF 3V3OUT RESET# USBDM USBDP 3V3OUT U1 10 VCC 1 VCCIO GND GND GND GND 3 13 17 FT230XQ CBUS0 CBUS1 CBUS2 CBUS3 TXD RXD RTS# CTS# 12 11 5 14 15 2 16 4 R3 2k R4 100k C11 1uF R5 1M 7 6 1 2 3 C8 0.1uF 3V3OUT CX/RX CX Q 5 GND CX/RX CX A B CLR U3 3V3OUT GND Q 5 1PPS R10 10k N.F. GND 74LVC1G123 0.1uF GND 7 6 1 2 3 3V3OUT R11 R12 10k 10k 0.1uF C12 0.1uF R6 1M GND C10 4.7uF C14 GND C9 0.1uF C13 GND GND 74LVC1G123 3V3OUT GND A B CLR U2 C7 0.1uF U4 AIC1747-18GU3 3 Vin Vout 2 1 Q1 IRLML6402 8 VCC GND 4 8 VCC GND 4 VBUS 1PPS GND 1 2 3 4 5 6 GP-2106 VCC GND 1PPS ON/OFF RX TX M1 2k R7 Q2 IRLML2502 GND R8 100k LED1 Blue R9 560R VBUS FPC/FFC cable 6-pin 0.5mm pitch CB1 503480-0600 1 2 3 4 5 6 CN2 AN_216 Using the FT230X to design a GPS Dongle Application Note Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 2 Example Circuit The schematic diagram below gives details of how the FT230XQ chip can be connected to a GPS receiver to create a USB based GPS sensor. In this case a GPS module – GP-2106 has been used. Figure 2.1 FT230XQ GPS Dongle circuit diagram 3 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 The FT230XQ (U1) provides the UART to USB conversion while GPS Module – GP-2106 (M1) provides location data in NMEA0183 v.3.01 format. For more information about GP-2106 GPS receiver please visit the product web site: http://www.adh-tech.com.tw/?gp-2106(sirf-star-iv),71 More information on the FT230XS may be obtained from the FTDI web page: http://www.ftdichip.com/Products/ICs/FT230X.html The implementation is straight-forward with TXD output from the FT230XQ connected to RXD input of the GP-2106 GPS receiver and RXD input of the FT230XQ connected to TXD output from the GP-2106. These connections form a data link between the GPS receiver and USB port. RTS# and CTS# pins of the FT230XQ are connected together to disable hardware flow control. To properly start-up the GPS receiver, power must be applied and ‘On’ pulse must be generated at pin-4 of the receiver. To satisfy this condition two monostable multivibrators (74LVC1G123) have been employed. First multivibrator U2 generates a delay during which the FT230XQ is enumerated by the USB host controller and power is applied to the GPS receiver. The second multivibrator generates an ‘On’ pulse (high level) which starts-up the chipset inside the GPS receiver module. Figure below illustrates the behaviour of the start-up circuit. Figure 2.2 Start-up circuit scope waveforms CH.1 (Yellow trace) was taken from the U1-pin-12 (CBUS0). CBUS0 is configured as an output of PWREN# signal. CH.2 (Blue trace) probe was connected to the ‘Q’ output of U2. CH.3 (Purple trace) probe was connected to the ‘Q’ output of U3. 4 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 The PWREN# pin toggles during the USB enumeration process and then it stays low as long as U1 is enumerated and the host computer is not in ‘sleep’ mode (i.e. it is not hibernated). A logic low level at this pin also enables the Q1 MOSFET transistor to conduct, feeding ‘VBUS’ (+5V) to the input of U4 voltage regulator. U4 reduces this voltage to 1.8V required by the GPS receiver. As soon as PWREN# pin goes low for the first time, U2 triggers, driving its output high. Approximately 1.6 seconds later U2 output will go low triggering U3 which will generate ‘On’ pulse at the ‘ON/OFF’ input of the GPS receiver. GPS dongle PCB has been equipped with the blue status LED (LED1). This LED will blink once a second when GPS fix is available (valid position has been acquired). LED1 is controlled by ‘1PPS’ output from GPS receiver through Q2 MOSFET transistor. 5 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 3 PCB Data FT230XQ GPS Dongle PCB files are available in Gerber format and Altium Designer project files and can be downloaded here: http://www.ftdichip.com/support/documents/schematics/HW_248_rev1_1.zip 6 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 4 Using FT230XQ GPS Dongle as a location sensor under Windows 7 To use FT230XQ GPS Dongle as a location sensor, a special driver must be installed. There are many location sensor drivers freely available on the web. One of them can be downloaded from following location: http://www.turboirc.com/gps7/ 7 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 5 Ordering Information Due to the large volume of interest expressed in this solution by FTDI customers, FTDI are delighted to offer a finished product, ready to use in a tough, contoured, hardened plastic enclosure. The module has a type A USB connector with dust cap for connecting to the USB host and will be powered from the USB host. Figure 5.1 FT-X-GPS Dongle Module Code Utilised IC Code Description FT-X-GPS FT230XQ USB GPS Dongle Table 5-1 – Ordering Information Drivers for the FT230X are available at: http://www.ftdichip.com/Drivers/VCP.htm 8 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 6 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 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 E-mail (Sales) E-mail (Support) E-mail (General Enquiries) [email protected] [email protected] m [email protected] China Tel: +86 21 62351596 Fax: +86 21 62351595 E-mail (Sales) E-mail (Support) E-mail (General Enquiries) [email protected] [email protected] [email protected] Web Site http://ftdichip.com 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 9 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 Appendix A – References Document References FT230XQ webpage: http://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT230X.pdf GP-2106 webpage: http://www.adh-tech.com.tw/?gp-2106(sirf-star-iv),71 Information on GPS system: http://en.wikipedia.org/wiki/Global_Positioning_System Information on Windows Location API: Acronyms and Abbreviations Terms Description GPS Global Positioning System LED Light Emitting Diode MOSFET Metal–Oxide–Semiconductor Field-Effect Transistor RXD Receive Data (The receive data line of RS232) TXD Transmit Data (The transmit data line of RS232) UART USB USB-IF Universal Asynchronous Receiver/Transmitter Universal Serial Bus USB Implementers Forum 10 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 Appendix B – List of Figures List of Figures Figure 2.1 FT230XQ GPS Dongle circuit diagram ..................................................................... 3 Figure 2.2 Start-up circuit scope waveforms ........................................................................... 4 Figure 5.1 FT-X-GPS Dongle ................................................................................................. 8 List of tables Table 5-1 – Ordering Information .......................................................................................... 8 11 Copyright © 2013 Future Technology Devices International Limited Application Note AN_216 Using the FT230X to design a GPS Dongle Version 1.1 Document Reference No.: FT_000698 Clearance No.: FTDI# 301 Appendix C – Revision History Document Title: AN_216 Using the FT230X to design a GPS Dongle Document Reference No.: FT_000698 Clearance No.: FTDI# 301 Product Page: http://www.ftdichip.com/Support.htm/FTReferenceDesigns.htm Document Feedback: Send Feedback Revision 1.0 Changes Date Initial Release 2012-07-09 Included details of dongle for retail. 1.1 Updated US contact details 2013-08-08 Added image in section 5 12 Copyright © 2013 Future Technology Devices International Limited