Application Note. Interfacing the Atrua Fingerprint Sensor to the ML696201/69Q6203 Series. Introduction. Contents of This Application Note

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1 Interfacing the Atrua Fingerprint Sensor to the ML696201/69Q6203 Series Introduction This application note provides an example to the user on interfacing Oki's ML696201/69Q6203 Series ARM946E based MCU to the Atrua Swipe Fingerprint Sensor - ATW200. It should be used in conjunction with the sample code available from Oki and Atrua. Some sample code is included that demonstrates how to configure the SSIO to communicate correctly with the sensor. The basic circuit diagram for connecting the Fingerprint sensor is shown in Figure 1-2 on page 4. It is assumed the reader is familiar with the ARM microcontroller, Oki's ML696201/69Q6203 Series, and fingerprint recognition technologies. Contents of This Application Note 1 Application Description and Implementation Memory Requirements ATW200 Sensor Interface Description of Oki's ML696201/69Q6203 Series ARM Microcontroller Description of Atrua's ATW200 Fingerprint Sensor Optimized for Embedded Devices ML696201/69Q6203 Series Sample Code for Interfacing to the Sensor.. 9 Revision History December 2005 Rev 1.0 Application Note

2 1 Application Description and Implementation Oki has developed a CPU board that supports the ML696201/69Q6203 Series. The ML69Q6203 CPU board has all the necessary resources to enable engineers to develop and debug their application (HS-USB, SDRAM, SRAM, HDD, JTAG, Flash etc.). For more details on the board please visit the Oki web site The order number for this board is ICD- SK(69Q6203CPUBRD-HDD). Atrua provides a prototyping board for the ATW200 fingerprint sensor. The board can be configured to support either SPI or parallel bus mode. Their prototyping board also has a header that allows easy connection between the sensor and the microcontroller. In this example the SSIO port on the ML696201/69Q6203 Series was used to interface to the Atrua fingerprint sensor. The Atrua sensor supports both SPI and a 8-bit parallel interface. The ML696201/69Q6203 Series SSIO port can be configured to operate in a SPI Master mode fashion. Since the SSIO port does not have a chip-select function, a GPIO is utilized for this purpose. In this application the GPIOE[13] was used for ease of wiring the board to the ML69Q6203 CPU Board. 1.1 Memory Requirements The memory requirements to run the compiled Navigation and Enrollment/Authentication algorithm are 75KB SRAM and 60KB ROM. If the Navigation feature is not required, then 64KB of SRAM is sufficient. Increasing the amount of memory beyond this does not influence the matching or enrollment times. The ML696201/69Q6203 Series features 128KB of 32-bit wide internal SRAM memory and also 512KB of internal Flash. This memory footprint can easily accommodate the requirements of the Atrua software without the need for any external components. It also leaves a lot of space for other application software to run if necessary. The ML696201/69Q6203 Series could easily be used as in fast Fingerprint access applications that utilize USB, HDD and NAND Flash. 1.2 ATW200 Sensor Interface The ATW200 sensor supports 1.8V-to-3.3V I/O and 2.5V-to-3.3V core voltage. This means it can be easily interfaced to the ML696201/69Q6203 Series I/O. Transfer data rates of up to 25 Mbps are possible with this sensor, Atrua recommends 6 Mbps in their documentation. The SSIO block of the ML696201/69Q6203 Series can achieve a maximum of 15 Mbps. The SSIO-1 is configured as a Master, transmitting least-significant-bit first. The sensor supports an interrupt output. Hence the sensor could be configured to wake up the MCU when a finger swipe is detected. The SSIO port on the ML696201/69Q6203 Series also has DMA functionality. The DMA mode is cycle stealing and supported only in SSIO master mode. An enhancement of this design would be to use the interrupt signal from the sensor to wake up the ML696201/69Q6203 Series device, and then DMA transfer the appropriate number of bytes (frame data) to the fingerprint algorithm engine for processing (navigation/enrollment/authentication). This function was not implemented in this design. The signal connections between the CPU board and the Atrua prototyping board are shown in Table 1-1. A typical connection diagram of the development system ia shown in Figure 1-1. Table 1-1. Connections Between the CPU Board and the Atrua Prototyping Board ATW200 ML69Q6203 CPU Board MOSI SSIOTXD1 (CN9.39) MISO SSIORXD1 (CN9.40) SCK SSIOCK1 (CN9.38) ncs GPIOE[13] (CN9.65) nintr GPIOE[14] (CN9.66) 2 Oki Semiconductor December 2005 Rev 1.0

3 Application Description and Implementation Figure 1-1. Typical Connection Diagram of the Development System The tools used in the development were from IAR - EWARM. Atrua provide a reference design package to assist in the integration of their technology. This consists of documentation, software and library files. Please contact Atrua for further information. These files are ported to the relevant MCU architecture, in this case ARM946E-S. Besides the essential library files there are three main files used to verify functionality of the system. The following is a description of the files: Testsensor.c Tests that the sensor can be accessed correctly Navtest.c Tests the Navigational features EnrVerTest.c Tests the Enrollment and Authentication features The oscilloscope shot shown in Figure 1-2 shows the basic communication between the ML69Q6203 and the ATW200 sensor over the SSIO-1 port. As can be seen here, after the ncs goes low, the SCK goes active. The data is sent lsb first from the ML69Q6203 over the MOSI line to the sensor. The first data sent is a command. The ML69Q6203 expects a reply from the slave, therefore the ML69Q6203 starts a second phase of SCK, and the MISO data is read into the SSIO block (on the second SCK phase the MOSI data is ignored by the sensor). Note that the SCK in this case is running at 15 MHz. Once the fingerprint sensor is correctly connected to the CPU board, the testsenor.c file is linked, compiled, downloaded, and run. Communication to the Host (PC) uses Hyperterm, so the serial port of the host and the ML69Q6203 must be appropriately configured. The resulting output on Hyperterm shows that the device was successfully recognized, and that test, reading, and writing also passed. Therefore, the sensor is correctly connected and working properly. Figure 1-3 shows the typical Host view during initial operation verification. December 2005 Rev 1.0 Oki Semiconductor 3

4 Figure 1-2. Basic Communication Between the Atrua Board and the ML69Q6203 CPU Board ncs SCK MOSI MISO Figure 1-3. Typical Host View During Initial Operation Verification Next the navtest.c file is linked into the build. Figure 1-4 shows the Hyperterm snapshot of the serial output from the system when the Navigation code is compiled and running. The sensor and associated algorithm can detect a finger swiping across the sensor in the X or Y direction, it can also detect the angle or Theta. 4 Oki Semiconductor December 2005 Rev 1.0

5 Application Description and Implementation Figure 1-4. Hyperterm Snapshot of the Serial Output from the System Figure 1-5 shows a snapshot of a finger swiped across the sensor when the EnrVerTest.c file is linked and run. The ridges and grooves of the fingerprint are clearly visible in the figure. Figure 1-5. Snapshot of a Finger Swiped Across the Sensor The Atrua software algorithm subsequently takes this snapshot and finds the minutiae at which point it will create a template (2KB File size). This template is stored by the system on Flash memory, for example, and can be later called up for Finger verification. Figure 1-6 shows a flow diagram for a fingerprint secured hard drive. The code was written for the Atrua sensor interfaced to the Oki ML69Q6203 CPU Board. PC access to the Hard drive via USB is only possible when the correct finger is swiped across the sensor. December 2005 Rev 1.0 Oki Semiconductor 5

6 Figure 1-6. Flow Diagram for a Fingerprint Secured Hard Drive Start cstratup_iar_mml69.s Initialization irq.c common.c IAR_re entrant_irq.s79 Setup Board and Memories for Sensor, ATA, and USB Is Sensor Present? NO Put "E" on 7-Segment Display Atrua_Oki.c EnrVertests.c Atrua libraries NO YES YES YES Enroll? (SW3 Depressed) Enroll Success NO Get stored Template from Internal Flash Put "C" on 7-Segment Display YES Verify Swipe NO Put "F" on 7-Segment Display, wait for SW3 to be pressed main_hddvbus_smp.c main_hddvbus.c Oki ATA, USB and DMA libraries YES Put "A" on 7-Segment Display, enable USB access to Hard Drive 6 Oki Semiconductor December 2005 Rev 1.0

7 Description of Oki's ML696201/69Q6203 Series ARM Microcontroller 2 Description of Oki's ML696201/69Q6203 Series ARM Microcontroller The ML696201/69Q6203 Series of microcontrollers is the latest in Oki Semiconductor's growing lineup of ARM products. As shown in Figure 2-1 these devices contain a 120 MHz ARM946E-S core with USB High Speed (480 Mbps) with PHY and ATA/IDE controller interfaces. This family supports Smart Media and NAND Flash devices. In addition, they also contain 128KBytes of 32-bit wide, zero wait state SRAM, 512KBytes of Flash (ML69Q6203 only), multiple serial channels (UART, 2 x SSIO, I 2 C and I 2 S) as well as multiple timers, A/D converters, RTC, PWM, WDT, and a flexible external memory controller. The ML696201/69Q6203 Series is available in a 272-pin LFBGA package (0.65mm) and is also available lead free. The integration of the ARM core (capable of executing either the 32-bit ARM or the 16-bit ARM THUMB instructions) with a robust peripheral set and low-power consumption on the ML696201/ 69Q6203 Series makes them the ideal parts for many DSP, USB, and mass storage type applications. Figure 2-1. ML696201/69Q6203 Series Block Diagram December 2005 Rev 1.0 Oki Semiconductor 7

8 3 Description of Atrua's ATW200 Fingerprint Sensor The Atrua Wings ATW200 is a sensor + software processing system. The system consists of: A small, low-cost, low-power sensor which provides information on fingerprint features and movement Algorithms which perform fingerprint recognition, navigation & control functions in a highly accurate, and CPU and memory efficient manner. Figure 3-1. Atrua's ATW200 Fingerprint Sensor The sensor creates partial images (frames) of the finger by sensing the ridges and valleys on the finger as it is swept across its surface. Internal circuits within the sensor die convert the sensed data into a stream of digital data (a frame) that is presented to the host microprocessor via a SPI interface or a 8-bit bidirectional bus interface compatible with most microprocessors. There are two key classes of algorithms that execute on the host, and they comprise the core functions of this haptic processing system: Fingerprint authentication Control & navigation. These algorithms operate on the data streamed from the sensor. The authentication algorithms extract the minutiae features used for fingerprint verification, and match the minutiae pattern to the user's template stored on the device. The navigation/control algorithms analyze finger motions to provide control functions. 3.1 Optimized for Embedded Devices Optimized for embedded devices, the low cost, small physical size and minimal power consumption of the Atrua Wings ATW200 simplify its integration into mobile phones and other small mobile devices. The ATW200 has an integrated analog-to-digital converter to digitize the sensed data, and an automatic gain control (AGC) function that provides high quality fingerprint images from all types of skin, dry to moist, in a wide range of climatic conditions, even hot and humid. The sensor features a low operating current, which can be further reduced by putting the device in standby mode when fingerprint 'swiping' is not being used. The ATW200 is provided in an LGA package. The sensor surface is protected by a special abrasion and chemical resistant coating to provide long life with high reliability. More information can be found at the Atrua web site Oki Semiconductor December 2005 Rev 1.0

9 ML696201/69Q6203 Series Sample Code for Interfacing to the Sensor 4 ML696201/69Q6203 Series Sample Code for Interfacing to the Sensor The following sample code is just a snippet of the code available from Oki. The sample code shows how to configure the SSIO-1 port of the ML696201/69Q6203 Series to communicate to the sensor via Master mode SPI. Sensor algorithm libraries for the ARM946E-S are available from Atrua - /*******************************************************************************/ // functions void init_ssio1(void) // Initialize SSIO1 void ssio1_send(ubyte, UBYTE) // Write to SSIO1 UBYTE ssio1_read(ubyte) // Read from SSIO1 int ssio1_bulk_read(unsigned int bytelen, unsigned char *buf) // read bulk data // global variables volatile unsigned char temp1 volatile unsigned char temp2 char *buf /****************************************************************************** * Initialize SSIO * Function : init_ssio * Parameters * Input : Nothing * Output : Nothing *****************************************************************************/ void init_ssio1(void) { /* Oki SSIO to Atrua sensor connections MOSI GPIOD 11 MISO GPIOD 12 SCLK GPIOD 13 ncs GPIOE 13 INTR GPIOE?? */ volatile UBYTE dummy // setup of PIOE13 set_wbit(gppme,0x2000 ) set_wbit(gppoe,0x2000 ) // GPIOE[13] is an output // ncs high to sensor put_wvalue(pioctl, CNFIG_UNLOCK) set_hbit(pioctl,0x3800) // SSIO1 muxed out /* * SSIOCON_MSBFST --- MSB first * SSIOCON_MASTER --- MASTER * SSIOCON_TCK0 --- select 15MHz clock * SSIOCON_TCK1 --- select 7.5MHz clock */ /* setup of SSIO1 */ put_wvalue(ssiocon1, SSIOCON_LSBFST SSIOCON_MASTER SSIOCON_TCK0) // set loopback test mode put_wvalue(ssiotscon1, SSIOTSCON_LBTST) December 2005 Rev 1.0 Oki Semiconductor 9

10 // clear status put_wvalue(ssiosta1, 0x00) // dummy write and read ssio1_send(0xff,0xff) dummy = ssio1_read(0xff) // reset loopback test mode put_wvalue(ssiotscon1, SSIOTSCON_NOTST) // clear interrupt bit put_wvalue(ssioint1, SSIOINT_TXRXCMP) } return /****************************************************************************** * Read bulk data from SSIO1 * Function : ssio1_bulk_read * Parameters * Input : int number of bytes to read * Output : *buf to store read data *****************************************************************************/ int ssio1_bulk_read(unsigned int bytelen, unsigned char *buf) { volatile int i=0 unsigned char cmd clr_wbit(gppoe,0x2000 ) cmd = DAT_REG<<1 SPI_CMD_READ put_wvalue(ssiobuf1, cmd) // ncs low to sensor // SSIOBUFx is 32bit // wait for receive complete temp1 = get_wvalue(ssiobuf1) put_wvalue(ssioint1, SSIOINT_TXRXCMP) // clear TXRXCMP bit for(i=0 i<bytelen-1 ++i){ put_wvalue(ssiobuf1, cmd) // write addr *buf++ = get_wvalue(ssiobuf1) put_wvalue(ssioint1, SSIOINT_TXRXCMP) // clean TXRXCMP bit } cmd = STA_REG<<1 SPI_CMD_READ put_wvalue(ssiobuf1, cmd) *buf = get_wvalue(ssiobuf1) put_wvalue(ssioint1, SSIOINT_TXRXCMP) // clean TXRXCMP bit set_wbit(gppoe,0x2000 ) // ncs hi to sensor } return ++i 10 Oki Semiconductor December 2005 Rev 1.0

11 ML696201/69Q6203 Series Sample Code for Interfacing to the Sensor /****************************************************************************** * SSIO1 data send * Function : ssio1_send * Parameters * Input : send data1, send_data2 * Output : Nothing *****************************************************************************/ void ssio1_send(ubyte send_data1, UBYTE send_data2) { volatile unsigned int i clr_wbit(gppoe,0x2000 ) // ncs low to sensor send_data1=send_data1<<1 put_wvalue(ssiobuf1, send_data1) temp1 = get_wvalue(ssiobuf1) put_wvalue(ssioint1, SSIOINT_TXRXCMP) // clear TXRXCMP bit put_wvalue(ssiobuf1, send_data2) temp2 = get_wvalue(ssiobuf1) put_wvalue(ssioint1, SSIOINT_TXRXCMP) // clear TXRXCMP bit } set_wbit(gppoe,0x2000 ) return // ncs high to sensor /****************************************************************************** * SSIO1 data read * Function : ssio1_read * Parameters * Input : read address * Output : char read data *****************************************************************************/ UBYTE ssio1_read(ubyte address) { volatile UBYTE temp_char volatile int i clr_wbit(gppoe,0x2000 ) // ncs low to sensor } address = address<<1 put_wvalue(ssiobuf1, address SPI_CMD_READ) temp_char = get_wvalue(ssiobuf1) put_wvalue(ssioint1, SSIOINT_TXRXCMP) // clear TXRXCMP bit put_wvalue(ssiobuf1, address SPI_CMD_READ) temp_char = get_wvalue(ssiobuf1) put_wvalue(ssioint1, SSIOINT_TXRXCMP) // clear TXRXCMP bit set_wbit(gppoe,0x2000 ) // ncs high to sensor return temp_char December 2005 Rev 1.0 Oki Semiconductor 11

12 Revision History Revision Date Changes Since Last Revision /14/2005 This is the initial release of this document. 12 Oki Semiconductor December 2005 Rev 1.0

13 Notice The information contained herein can change without notice owing to product and/ or technical improvements. Please make sure before using the product that the information you are referring to is up-to-date. The outline of action and examples of application circuits described herein have been chosen as an explanation of the standard action and performance of the product. When you actually plan to use the product, please ensure that the outside conditions are reflected in the actual circuit and assembly designs. Oki assumes no responsibility or liability whatsoever for any failure or unusual or unexpected operation resulting from misuse, neglect, improper installation, repair, alteration or accident, improper handling, or unusual physical or electrical stress including, but not limited to, exposure to parameters outside the specified maximum ratings or operation outside the specified operating range. Neither indemnity against nor license of a third party's industrial and intellectual property right,etc.is granted by us in connection with the use of product and/or the information and drawings contained herein. No responsibility is assumed by us for any infringement of a third party's right which may result from the use thereof. When designing your product, please use our product below the specified maximum ratings and within the specified operating ranges, including but not limited to operating voltage, power dissipation, and operating temperature. The products listed in this document are intended for use in general electronics equipment for commercial applications (e.g., office automation, communication equipment, measurement equipment, consumer electronics, etc.). These products are not, unless specifically authorized by Oki, authorized for use in any system or application that requires special or enhanced quality and reliability characteristics nor in any system or application where the failure of such system or application may result in the loss or damage of property, or death or injury to humans. Such applications include, but are not limited to: traffic control, automotive, safety, aerospace, nuclear power control, and medical, including life support and maintenance. Certain parts in this document may need governmental approval before they can be exported to certain countries. The purchaser assumes the responsibility of determining the legality of export of these parts and will take appropriate and necessary steps, at their own expense, for export to another country. Oki Semiconductor reserves the right to make changes in specifications at anytime and without notice. This information furnished by Oki Semiconductor in this publication is believed to be accurate and reliable. However, no responsibility is assumed by Oki Semiconductor for its use nor for any infringements of patents or other rights of third parties resulting from its use. No license is granted under any patents or patent rights of Oki. Trademarks: Advantage and µplat are trademarks of Oki Semiconductor. ARM, ARM7TDMI, and the ARM Powered Logo are registered trademarks, and AMBA, ARM7, and Multi-ICE are trademarks of Advanced RISC Machines, Ltd. Copyright 2004 and 2005 Oki Semiconductor Regional Sales Offices Semiconductor Products Northwest Area 785 N. Mary Avenue Sunnyvale, CA Tel: 408/ Fax: 408/ Northeast Area Shattuck Office Center 138 River Road Andover, MA Tel: 978/ Fax: 978/ North Central Area 1450 East American Lane, Suite 1400 Schaumburg, IL Tel: 847/ / Fax: 847/ Southwest and South Central Area 1902 Wright Place, Suite 200 Carlsbad, CA Tel: 760/ Fax: 760/ Southeast Area 4800 Whitesburg Drive # 30 PMB 263 Huntsville, AL Tel: 256/ Fax: 408/ Oki Web Site: December 2005, Rev 1.0 Corporate Headquarters 785 N. Mary Avenue Sunnyvale, CA Tel: 408/ Fax: 408/