AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER AR1000 Series Resistive Touch Screen Controller Special Features Touch Sensor Support • • • • • • • • • RoHS Compliant Power-Saving Sleep mode Industrial Temperature Range Built-in Drift Compensation Algorithm 128 Bytes of User EEPROM Power Requirements • Operating Voltage: 2.5-5.0V ±5% • Standby Current: - 5V: 85 µA, typical; 125 µA (maximum) - 2.5V: 40 µA, typical; 60 µA (maximum) • Operating “No touch” Current: - 3.0 mA (typical) • Operating “Touch” Current: - 17 mA, typical, with a touch sensor having 200 layers - Actual current is dependent on the touch sensor used • AR1011/AR1021 Brown-Out Detection (BOR) set to 2.2V 4-Wire, 5-Wire and 8-Wire Analog Resistive Lead-to-Lead Resistance: 50-2,000typical) Layer-to-Layer Capacitance: 0-0.5 µF Touch Sensor Time Constant: 500 µs (maximum) Touch Resolution • 10-bit Resolution (maximum) Touch Coordinate Report Rate • 140 Reports Per Second (typical) with a Touch Sensor of 0.02 µF with 200 Layers • Actual Report Rate is dependent on the Touch Sensor used Communications • • • SPI, Slave mode, p/n AR1021 I2C, Slave mode, p/n, AR1021 UART, 9600 Baud Rate, p/n AR1011 Touch Modes • Off, Stream, Down, Up and more. 2009-2016 Microchip Technology Inc. DS40001393C-page 1 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER Table of Contents 1.0 Device Overview .......................................................................................................................................................................... 3 2.0 Basics of Resistive Sensors ......................................................................................................................................................... 5 3.0 Hardware...................................................................................................................................................................................... 9 4.0 I2C Communications .................................................................................................................................................................. 14 5.0 SPI Communications .................................................................................................................................................................. 18 6.0 UART Communications .............................................................................................................................................................. 22 7.0 Touch Reporting Protocol ........................................................................................................................................................... 23 8.0 Configuration Registers .............................................................................................................................................................. 24 9.0 Commands ................................................................................................................................................................................. 30 10.0 Application Notes ....................................................................................................................................................................... 39 11.0 Electrical Specifications .............................................................................................................................................................. 45 12.0 Packaging Information................................................................................................................................................................ 47 Appendix A: Data Sheet Revision History............................................................................................................................................ 57 Appendix B: Device Differences........................................................................................................................................................... 58 The Microchip Website......................................................................................................................................................................... 59 Customer Change Notification Service ................................................................................................................................................ 59 Customer Support ................................................................................................................................................................................ 59 TO OUR VALUED CUSTOMERS It is our intention to provide our valued customers with the best documentation possible to ensure successful use of your Microchip products. To this end, we will continue to improve our publications to better suit your needs. Our publications will be refined and enhanced as new volumes and updates are introduced. If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via E-mail at [email protected]. We welcome your feedback. Most Current Data Sheet To obtain the most up-to-date version of this data sheet, please register at our Worldwide Website at: http://www.microchip.com You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page. The last character of the literature number is the version number, (e.g., DS30000000A is version A of document DS30000000). Errata An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision of silicon and revision of document to which it applies. To determine if an errata sheet exists for a particular device, please check with one of the following: • Microchip’s Worldwide Website; http://www.microchip.com • Your local Microchip sales office (see last page) When contacting a sales office, please specify which device, revision of silicon and data sheet (include literature number) you are using. Customer Notification System Register on our website at www.microchip.com to receive the most current information on all of our products. DS40001393C-page 2 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 1.0 DEVICE OVERVIEW 1.1 The Microchip mTouch® AR1000 Series Resistive Touch Screen Controller is a complete, easy to integrate, cost-effective and universal touch screen controller chip. The AR1000 Series has sophisticated proprietary touch screen decoding algorithms to process all touch data, saving the host from the processing overhead. Providing filtering capabilities beyond that of other low-cost devices, the AR1000 delivers reliable, validated, and calibrated touch coordinates. Using the on-board EEPROM, the AR1000 can store and independently apply the calibration to the touch coordinates before sending them to the host. This unique combination of features makes the AR1000 the most resource-efficient touch screen controller for system designs, including embedded system integrations. FIGURE 1-1: BLOCK DIAGRAM FIGURE 1-2: PIN DIAGRAM Applications The AR1000 Series is designed for high volume, small form factor touch solutions with quick time to market requirements – including, but not limited to: • • • • • • • • Mobile communication devices Personal Digital Assistants (PDA) Global Positioning Systems (GPS) Touch Screen Monitors KIOSK Media Players Portable Instruments Point of Sale Terminals AR1000 Series (QFN) VDD M1 SYM2 WAKE SIQ SY+ SS SDO NC VSS XX+ 5WSXYY+ SX+ SDI/SDA/RX NC SCK/SCL/TX 2009-2016 Microchip Technology Inc. 20 19 18 17 16 15 14 13 12 11 1 2 3 4 5 M2 WAKE SIQ SY+ SS 6 SDO 7 NC 8 SCK/SCL/TX 9 NC 10 SDI/SDA/RX 1 2 3 4 5 6 7 8 9 10 SYM1 VDD VSS X- 20 19 18 17 16 AR1000 Series (SSOP, SOIC) X+ 15 5WSX- 14 Y- 13 Y+ 12 SX+ 11 DS40001393C-page 3 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER TABLE 1-1: PIN DESCRIPTIONS Pin Function SSOP, SOIC Description/Comments QFN 1 18 VDD Supply Voltage 2 19 M1 Communication Selection 3 20 SY- Sense Y- (8-wire). Tie to VSS, if not used. 4 1 M2 4/8-wire or 5-wire Sensor Selection 5 2 WAKE 6 3 SIQ LED Drive/SPI Interrupt. No connect, if not used. 7 4 SY+ Sense Y+ (8-wire). Tie to VSS, if not used. 8 5 SS Slave Select (SPI). Tie to VSS, if not used. 9 6 SDO 10 7 NC 11 8 SCK/SCL/TX 12 9 NC 13 10 SDI/SDA/RX I2C Serial Data/SPI Serial Data Input/UART Receive 14 11 SX+ Sense X+ (8-wire). Tie to VSS, if not used. 15 12 Y+ Y+ Drive 16 13 Y- Y- Drive 17 14 5WSX- 18 15 X+ X+ Drive X- Drive 19 16 X- 20 17 VSS DS40001393C-page 4 Touch Wake-up/Touch Detection SPI Serial Data Output/I2C Interrupt. Tie to Vss, if UART. No connection. No connect or tie to VSS or VDD. SPI/I2C Serial Clock/UART Transmit No connection. No connect or tie to VSS or VDD. 5W Sense (5-wire)/Sense X(8-wire). Tie to VSS, if not used. Supply Voltage Ground 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 2.0 BASICS OF RESISTIVE SENSORS TABLE 2-1: Sensor 2.1 Terminology Less expensive than 5-wire or 8-wire Lower power than 5-wire More linear (without correction) than 5-wire Touch inaccuracies occur from flex layer damage or resistance changes 5-Wire Maintains touch accuracy with flex layer damage Inherent nonlinearity often requires touch data correction Touch inaccuracies occur from resistance changes 8-Wire More expensive than 4-wire Lower power than 5-wire More linear (without correction) than 5-wire Touch inaccuracies occur from flex layer damaged Maintains touch accuracy with resistance changes Stable or Glass is the bottom sensor layer that interfaces against the display. Spacer Adhesive is a frame of adhesive that connects the flex and stable layers together around the perimeter of the sensor. Spacer Dots maintain physical and electrical separation between the flex and stable layers. The dots are typically printed onto the stable layer. Bus Bars or Silver Frit electrically connect the ITO on the flex and stable layers to the sensor’s interface tail. Bus bars are typically screen printed silver ink. They are typically much lower in resistivity than the ITO. X-Axis is the left and right direction on the touch sensor. Y-Axis is the top and bottom direction on the touch sensor. Drive Lines supply a voltage gradient across the sensor. 2.2 General Resistive 4, 5, and 8-wire touch sensors consist of two facing conductive layers, held in physical separation from each other. The force of a touch causes the top layer to deflect and make electrical contact with the bottom layer. Comments 4-Wire ITO (Indium Tin Oxide) is the resistive coating that makes up the active area of the touch sensor. ITO is a transparent semiconductor that is sputtered onto the touch sensor layers. Flex or Film or Topsheet is the top sensor layer that a user touches. Flex refers to the fact that the top layer physically flexes from the pressure of a touch. SENSOR COMPARISON The AR1000 Series Resistive Touch Screen Controllers will work with any manufacturers of analog resistive 4, 5 and 8-wire touch screens. The communications and decoding are included, allowing the user the quickest simplest method of interfacing analog resistive touch screens into their applications. The AR1000 Series was designed with an understanding of the materials and processes that make up resistive touch screens. The AR1000 Series Touch Controller is not only reliable, but can enhance the reliability and longevity of the resistive touch screen, due to its advanced filtering algorithms and wide range of operation. Touch position measurements are made by applying a voltage gradient across a layer or axis of the touch sensor. The touch position voltage for the axis can be measured using the opposing layer. A comparison of typical sensor constructions is shown below in Table 2-1. 2009-2016 Microchip Technology Inc. DS40001393C-page 5 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 2.3 4-Wire Sensor A 4-wire resistive touch sensor consists of a stable and flex layer, electrically separated by spacer dots. The layers are assembled perpendicular to each other. The touch position is determined by first applying a voltage gradient across the flex layer and using the stable layer to measure the flex layer’s touch position voltage. The second step is applying a voltage gradient across the stable layer and using the flex layer to measure the stable layer’s touch position voltage. The measured voltage at any position across a driven axis is predictable. A touch moving in the direction of the driven axis will yield a linearly changing voltage. A touch moving perpendicular to the driven axis will yield a relatively unchanging voltage (See Figure 2-1). FIGURE 2-1: DS40001393C-page 6 4-WIRE DECODING 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 2.4 8-Wire Sensor An 8-wire resistive touch sensor consists of a stable and flex layer, electrically separated by spacer dots. The layers are assembled perpendicular to each other. The touch position is determined by first applying a voltage gradient across the flex layer and using the stable layer to measure the flex layer’s touch position voltage. The second step is applying a voltage gradient across the stable layer and using the flex layer to measure the stable layer’s touch position voltage. The measured voltage at any position across a driven axis is predictable. A touch moving in the direction of the driven axis will yield a linearly changing voltage. A touch moving perpendicular to the driven axis will yield a relatively unchanging voltage. FIGURE 2-2: The basic decoding of an 8-wire sensor is similar to a 4-wire. The difference is that an 8-wire sensor has four additional interconnects used to reference sensor voltage back to the controller. A touch system may experience voltage losses due to resistance changes in the bus bars and connection between the controller and sensor. The losses can vary with product use, temperature, and humidity. In a 4-wire sensor, variations in the losses manifest themselves as error or drift in the reported touch location. The four additional sense lines found on 8-wire sensors are added to dynamically reference the voltage to correct for this fluctuation during use (See Figure 2-2). 8-WIRE DECODING 2009-2016 Microchip Technology Inc. DS40001393C-page 7 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 2.5 5-Wire Sensor A 5-wire resistive touch sensor consists of a flex and stable layer, electrically separated by spacer dots. The touch position is determined by first applying a voltage gradient across the stable layer in the X-axis direction and using the flex layer to measure the axis touch position voltage. The second step is applying a voltage gradient across the stable layer in the Y-axis direction and using the flex layer to measure the axis touch position voltage. The voltage is not directly applied to the edges of the active layer, as it is for 4-wire and 8-wire sensors. The voltage is applied to the corners of a 5-wire sensor. FIGURE 2-3: DS40001393C-page 8 To measure the X-axis, the left edge of the layer is driven with 0V (ground), using connections to the upper left and lower left sensor corners. The right edge is driven with +5 VDC, using connections to the upper right and lower right sensor corners. To measure the Y-axis, the top edge of the layer is driven with 0V (ground), using connections to the upper left and upper right sensor corners. The bottom edge is driven with +5 VDC, using connections to the lower left and lower right sensor corners. The measured voltage at any position across a driven axis is predictable. A touch moving in the direction of the driven axis will yield a linearly changing voltage. A touch moving perpendicular to the driven axis will yield a relatively unchanging voltage (See Figure 2-3). 5-Wire Decoding 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 3.0 HARDWARE 3.1 Main Schematic A main application schematic for the SOIC/SSOP package pinout is shown in Figure 3-1. See Figure 1-2 for the QFN package pinout. FIGURE 3-1: MAIN SCHEMATIC (SOIC/SSOP PACKAGE PINOUT) 2009-2016 Microchip Technology Inc. DS40001393C-page 9 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 3.2 4, 5, 8-Wire Sensor Selection The desired sensor type of 4/8-wire or 5-wire is hardware selectable using pin M2. TABLE 3-1: 4/8-WIRE vs. 5-WIRE SELECTION Type M2 pin 4/8-wire VSS 5-wire VDD If 4/8-wire has been hardware-selected, then the choice of 4-wire or 8-wire is software-selectable via the TouchOptions Configuration register. When 4/8-wire is hardware-selected, the controller defaults to 4-wire operation. If 8-wire operation is desired, then the TouchOptions Configuration register must be changed. FIGURE 3-2: 3.3 4-Wire Touch Sensor Interface Sensor tail pinouts can vary by manufacturer and part number. Ensure that both sensor tail pins for one sensor axis (layer) are connected to the controller’s X-/X+ pins and the tail pins for the other sensor axis (layer) are connected to the controller’s Y-/Y+ pins. The controller’s X-/X+ and Y-/Y+ pin pairs do not need to connect to a specific sensor axis. The orientation of controller pins X- and X+ to the two sides of a given sensor axis is not important. Likewise, the orientation of controller pins Y- and Y+ to the two sides of the other sensor axis is not important. Connections to a 4-wire touch sensor are as follows (See Figure 3-2). 4-WIRE TOUCH SENSOR INTERFACE Tie unused controller pins 5WSX-, SX+, SY-, and SY+ to VSS. See Section 3.8 “ESD Considerations” and Section 3.9 “Noise Considerations” for important information regarding the capacitance of the controller schematic hardware. DS40001393C-page 10 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 3.4 5-Wire Touch Sensor Interface Sensor tail pinouts can vary by manufacturer and part number. Ensure sensor tail pins for one pair of diagonally related sensor corners are connected to the controller’s X-/X+ pins and the tail pins for the other pair of diagonally related corners are connected to the controller’s Y-/Y+ pins. The controller’s X-/X+ and Y-/Y+ pin pairs do not need to connect to a specific sensor axis. The orientation of controller pins X- and X+ to the two selected diagonal sensor corners is not important. Likewise, the orientation of controller pins Y- and Y+ to the other two selected diagonal sensor corners is not important. The sensor tail pin connected to its top layer must be connected to the controller’s 5WSX- pin. Connections to a 5-wire touch sensor are shown in Figure 3-3 below. FIGURE 3-3: 5-WIRE TOUCH SENSOR INTERFACE Tie unused controller pins SX+, SY-, and SY+ to VSS. See “Section 3.8 “ESD Considerations” and Section 3.9 “Noise Considerations” for important information regarding the capacitance of the controller schematic hardware. 2009-2016 Microchip Technology Inc. DS40001393C-page 11 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 3.5 8-Wire Touch Sensor Interface Sensor tail pinouts can vary by manufacturer and part number. Ensure both sensor tail pins for one sensor axis (layer) are connected to the controller’s X-/X+ pins and the tail pins for the other sensor axis (layer) are connected to the controller’s Y-/Y+ pins. The controller’s X-/X+ and Y-/Y+ pin pairs do not need to connect to a specific sensor axis. The orientation of controller pins X- and X+ to the two sides of a given sensor axis is not important. Likewise, the orientation of controller pins Y- and Y+ to the two sides of the other sensor axis is not important. The 8-wire sensor differs from a 4-wire sensor in that each edge of an 8-wire sensor has a secondary connection brought to the sensor’s tail. These secondary connections are referred to as “sense” lines. The controller pins associated with the sense line for an 8-wire sensor contain an ‘S’ prefix in their respective names. For example, the SY- pin is the sense line connection associated with the main Y- pin connection. FIGURE 3-4: Consult with the sensor manufacturer’s specification to determine which member of each edge connected pair is the special 8-wire “sense” connection. Incorrectly connecting the sense and excite lines to the controller will adversely affect performance. The controller requires that the main and “sense” tail pin pairs for sensor edges be connected to controller pin pairs as follows: • • • • Y- and SYY+ and SY+ X- and 5WSXX+ and SX+ Connections to a 8-wire touch sensor are shown in Figure 3-4 below. 8-WIRE TOUCH SENSOR INTERFACE See Section 3.8 “ESD Considerations” and Section 3.9 “Noise Considerations” for important information regarding the capacitance of the controller schematic hardware. DS40001393C-page 12 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 3.6 Status LED 3.8 ESD Considerations The LED and associated resistor are optional. ESD protection is shown on the 4-wire, 5-wire, and 8-wire interface applications schematics. FIGURE 3-5: The capacitance of alternate ESD diodes may adversely affect touch performance. A lower capacitance is better. The PESD5V0S1BA parts shown in the reference design have a typical capacitance of 35 pF. Test to ensure that selected ESD protection does not degrade touch performance. LED SCHEMATIC The LED serves as a status indicator that the controller is functioning. It will slow flash when the controller is running with no touch in progress. It will flicker quickly (mid-level on) when a touch is in progress. If the LED is used with SPI communication, then the LED will be off with no touch and flicker quickly (mid-level on) when a touch is in progress. Note: 3.7 If the SIQ pin is not used, it must be left as a No Connect and NOT tied to circuit VDD or VSS. ESD protection is shown in the reference design, but acceptable protection is dependent on your specific application. Ensure your ESD solution meets your design requirements. 3.9 Noise Considerations Touch sensor filtering capacitors are included in the reference design. Warning: Changing the value of the capacitors may adversely affect performance of the touch system. WAKE Pin The AR1000’s WAKE pin is described as “Touch Wake-Up/Touch Detection”. It serves the following three roles in the controller’s functionality: • Wake-up from touch • Touch detection • Measure sensor capacitance The application circuit shows a 20 KΩ resistor connected between the WAKE pin and the X- pin on the controller chip. The resistor is required for product operation, based on all three of the above roles. 2009-2016 Microchip Technology Inc. DS40001393C-page 13 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER I2C COMMUNICATIONS 4.0 The AR1021 is an I2C slave device with a 7-bit address of 0x4D, supporting up to 400 kHz bit rate. A master (host) device interfaces with the AR1021. I2C Hardware Interface 4.1 A summary of the hardware interface pins is shown below in Table 4-1. TABLE 4-1: I2C HARDWARE INTERFACE AR1021 Pin Description M1 Connect to VSS to select I2C communications SCL Serial Clock SDA Serial Data SDO Data ready interrupt output to master M1 Pin • The M1 pin must be connected to VSS to configure the AR1021 for I2C communications. SCL Pin • The SCL (Serial Clock) pin is electrically open-drain and requires a pull-up resistor, typically 2.2 K to 10 K, from SCL to VDD. • SCL Idle state is high. SDA Pin • The SDA (Serial Data) pin is electrically open-drain and requires a pull-up resistor, typically 2.2 K to 10 K, from SDA to VDD. • SDA Idle state is high. • Master write data is latched in on SCL rising edges. • Master read data is latched out on SCL falling edges to ensure it is valid during the subsequent SCL high time. SDO Pin • The SDO pin is a driven output interrupt to the master. • SDO Idle state is low. • SDO will be asserted high when the AR1021 has data ready (touch report or command response) for the master to read. DS40001393C-page 14 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER I2C Pin Voltage Level Characteristics 4.2 I2C PIN VOLTAGE LEVEL CHARACTERISTICS TABLE 4-2: Function Pin Input Output SCL/SCK SCL/SCK/TX VSS ≤ VIL≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD — SDO SDO — VSS ≤ VOL(1) ≤ (1.2V – 0.15*VDD)(2) (1.25*VDD – 2.25V)(3) ≤ VOH(1) ≤ VDD SDA SDI/SDA/RX VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD Open-drain Note 1: 2: 3: 4.3 These parameters are characterized but not tested. At 10 mA. At –4 mA. Addressing The AR1021’s device ID 7-bit address is: 0x4D (0b1001101) Device ID Address, 7-bit A6 A5 A4 A3 A2 A1 1 0 0 1 1 0 1 TABLE 4-4: I2C DEVICE WRITE ID ADDRESS A7 A6 A5 A4 A3 1 0 0 1 1 FIGURE 4-1: A2 A1 A0 0 1 0 0x9A A5 A4 A3 1 0 0 1 1 A2 A1 A0 0 1 1 0x9B Master Read Bit Timing Master read is to receive touch reports and command responses from the AR1021. • Address bits are latched into the AR1021 on the rising edges of SCL. • Data bits are latched out of the AR1021 on the rising edges of SCL. • ACK is presented (by AR1021 for address, by master for data) on the ninth clock. • The master must monitor the SCL pin prior to asserting another clock pulse, as the AR1021 may be holding off the master by stretching the clock. I2C MASTER READ BIT TIMING DIAGRAM Steps 3. A6 4.4 A7 I2C DEVICE READ ID ADDRESS A7 I2C DEVICE ID ADDRESS TABLE 4-3: 1. 2. TABLE 4-5: SCL and SDA lines are Idle high. Master presents “Start” bit to the AR1021 by taking SDA high-to-low, followed by taking SCL high-to-low. Master presents 7-bit Address, followed by a R/W = 1 (Read mode) bit to the AR1021 on SDA, at the rising edge of eight master clock (SCL) cycles. 2009-2016 Microchip Technology Inc. 4. 5. AR1021 compares the received address to its device ID. If they match, the AR1021 acknowledges (ACK) the master sent address by presenting a low on SDA, followed by a low-high-low on SCL. Master monitors SCL, as the AR1021 may be “clock stretching”, holding SCL low to indicate that the master should wait. DS40001393C-page 15 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 6. Master receives eight data bits (MSb first) presented on SDA by the AR1021, at eight sequential master clock (SCL) cycles. The data is latched out on SCL falling edges to ensure it is valid during the subsequent SCL high time. 7. If data transfer is not complete, then: - Master acknowledges (ACK) reception of the eight data bits by presenting a low on SDA, followed by a low-high-low on SCL. - Go to step 5. 8. If data transfer is complete, then: - Master acknowledges (ACK) reception of the eight data bits and a completed data transfer by presenting a high on SDA, followed by a low-high-low on SCL. FIGURE 4-2: 9. 4.5 Master presents a “Stop” bit to the AR1021 by taking SCL low-high, followed by taking SDA low-to-high. Master Write Bit Timing Master write is to send supported commands to the AR1021. • Address bits are latched into the AR1021 on the rising edges of SCL. • Data bits are latched into the AR1021 on the rising edges of SCL. • ACK is presented by AR1021 on the ninth clock. • The master must monitor the SCL pin prior to asserting another clock pulse, as the AR1021 may be holding off the master by stretching the clock. I2C MASTER WRITE BIT TIMING DIAGRAM Steps 4.6 1. 2. The master normally controls the clock line SCL. Clock stretching is when the slave device holds the SCL line low, indicating to the master that it is not ready to continue the communications. 3. 4. 5. 6. 7. 8. 9. SCL and SDA lines are Idle high. Master presents “Start” bit to the AR1021 by taking SDA high-to-low, followed by taking SCL high-to-low. Master presents 7-bit Address, followed by a R/W = 0 (Write mode) bit to the AR1021 on SDA, at the rising edge of eight master clock (SCL) cycles. AR1021 compares the received address to its device ID. If they match, the AR1021 acknowledges (ACK) the master sent address by presenting a low on SDA, followed by a low-high-low on SCL. Master monitors SCL, as the AR1021 may be “clock stretching”, holding SCL low to indicate the master should wait. Master presents eight data bits (MSb first) to the AR1021 on SDA, at the rising edge of eight master clock (SCL) cycles. AR1021 acknowledges (ACK) receipt of the eight data bits by presenting a low on SDA, followed by a low-high-low on SCL. If data transfer is not complete, then go to step 5. Master presents a “Stop” bit to the AR1021 by taking SCL low-high, followed by taking SDA low-to-high. DS40001393C-page 16 Clock Stretching During communications, the AR1021 may hold off the master by stretching the clock with a low on SCL. The master must monitor the slave SCL pin to ensure the AR1021 is not holding it low, prior to asserting another clock pulse for transmitting or receiving. 4.7 AR1020 Write Conditions The AR1020 part does not implement clock stretching on write conditions. A 50 us delay is needed before the Stop bit, when clocking a command to the AR1020. 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 4.8 Touch Report Protocol Touch coordinates, when available, are provided to the master by the AR1021 in the following protocol (See Figure 4-3). FIGURE 4-3: I2C TOUCH REPORT PROTOCOL Note that the IRQ signal shown above occurs on the SDO pin of the AR1021. 4.9 Command Protocol The master issues supported commands to the AR1021 in the following protocol. Below is an example of the ENABLE_TOUCH command (see Figure 4-4). FIGURE 4-4: I2C COMMAND PROTOCOL Note that the IRQ shown above occurs on the SDO pin. 4.10 • 0x9A • 0x00 Pending communications are not maintained through a sleep/wake cycle. • 0x55 • 0x01 • 0x12 AR1021 Device ID address Protocol command byte (send 0x00 for the protocol command register) Header Data size Command 2009-2016 Microchip Technology Inc. Sleep State If the SDO pin is asserted for a pending touch report or command response, and the AR1021 enters a Sleep state, prior to the master performing a read on the data, then the data is lost. DS40001393C-page 17 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 5.0 SPI COMMUNICATIONS SPI operates in Slave mode with an Idle low SCK and data transmitted on the SCK falling edge. 5.1 SPI Hardware Interface A summary of the hardware interface pins is shown below in Table 5-1. TABLE 5-1: SPI HARDWARE INTERFACE AR1021 Pin Description M1 Connect to VDD to select SPI communications SDI Serial data sent from master SCK Serial clock from master SDO Serial data to master SPI SIQ Interrupt output to master (optional) SS Slave Select (optional) SCK Pin SS Pin • The AR1021 controller’s SCL/SCK/TX pin receives Serial Clock (SCK), controlled by the host. • The Idle state of the SCK should be low. • Data is transmitted on the falling edge of SCK. • The AR1021 controller’s SS pin provides optional “slave select” functionality. SDI Pin • The AR1021 controller’s SDI/SDA/RX pin reads Serial Data Input (SDI), sent by the host. SDO Pin • The AR1021 controller’s SDO pin presents Serial Data Output (SDO) to the host. SS Pin Level AR1021 Select VSS Active VDD Inactive In the ‘inactive’ state, the controller’s SDO pin presents a high-impedance in order to prevent bus contention with another device on the SPI bus. SIQ Pin • The AR1021 controller’s SIQ pin provides an optional interrupt output from the controller to the host. • The SIQ pin is asserted high when the controller has data available (a touch report or a command response) for the host. • The SIQ pin is deasserted after the host clocks out the first byte of the data packet. Note: The AR1000 Development kit PICkit™ Serial Pin 1 is designated for the SIQ interrupt pin after the firmware updated is executed for the PICkit. DS40001393C-page 18 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 5.2 SPI Pin Voltage Level Characteristics TABLE 5-2: SPI PIN VOLTAGE CHARACTERISTICS Operating Voltage: 2.5V ≤ VDD ≤ 5.25V Function Pin Input Output SCK SCL/SCK/TX VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD — SDI SDI/SDA/RX VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD — SDO SDO — VSS ≤ VOL(1) ≤ (1.2V – 0.15*VDD)(2) (1.25*VDD – 2.25V)(3) ≤ VOH(1) ≤ VDD SIQ SIQ — VSS ≤ VOL(1) ≤ (1.2V – 0.15*VDD)(2) (1.25*VDD – 2.25V)(3) ≤ VOH(1) ≤ VDD SS SS VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD Note 1: 2: 3: 5.3 These parameters are characterized but not tested. At 10 mA. At -4 mA. Data Flow 5.4 Touch Report Protocol SPI data is transferred by the host clocking the AR1021 controller’s Serial Clock (SCK) pin. The AR1021 controller’s touch reporting is interrupt driven: Each host driven clock cycle simultaneously shifts a bit of data into and out from the AR1021 controller: • The AR1021 controller asserts the SIQ interrupt pin high when it has a touch report ready. • The host clocks out the bytes of the touch report packet from the AR1021 controller. • The AR1021 controller clears the SIQ interrupt pin low, after the first byte of the touch report packet has been clocked out by the host. • Out from the AR1021 controller’s Serial Data Out (SDO) line. • Into the AR1021 controller’s Serial Data In (SDI) line. The data is shifted Most Significant bit (MSb) first. If the host clocks data out from the AR1021 controller when no valid data is available, then a byte value of 0x4d will be presented by the controller. FIGURE 5-1: The communication protocol for the AR1021 controller reporting touches to the host as shown below in Figure 5-1. SPI TOUCH REPORT PROTOCOL 2009-2016 Microchip Technology Inc. DS40001393C-page 19 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 5.5 Command Protocol The AR1021 controller receives commands from the host as follows: • The host clocks the bytes of a command to the AR1021 controller. • The AR1021 controller asserts the SIQ interrupt pin high when it is ready with a response to the command sent by the host. FIGURE 5-2: 5.6 • The host clocks out the bytes of the command response from the AR1021 controller. • The AR1021 controller clears the SIQ interrupt pin low, after the first byte of the command response has been clocked out by the host. The communication protocol for the host sending the ENABLE_TOUCH command to the AR1021 controller is shown below in Figure 5-2. SPI TIMING DIAGRAM – COMMAND PROTOCOL (ENABLE_TOUCH) SPI Bit Timing – General General timing waveforms are shown below in Figure 5-3. FIGURE 5-3: DS40001393C-page 20 SPI GENERAL BIT TIMING WAVEFORM 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 5.7 Timing – Bit Details 5.7.1 BIT RATE The SPI standard does not specify a maximum data rate for the serial bus. In general, SPI data rates can be in MHz. Peripherals devices, such as the AR1021 controller, specify their own unique maximum SPI data rates. The maximum SPI bit rate for the AR1021 controller is ~900 kHz. 5.7.2 INTER-BYTE DELAY The AR1021 controller requires an inter-byte delay of ~50 us. This means the host should wait ~50 us between the end of clocking a given byte and the start of clocking the next byte. 5.7.3 BIT TIMING – DETAIL Characterized timing details are shown below, in Figure 5-4. Characterization has been performed at bit rates of ~39 kHz and ~156 kHz. FIGURE 5-4: TABLE 5-3: SPI BIT TIMING – DETAIL SPI BIT TIMING MIN. AND MAX. VALUES Parameter Number(1) Parameter Description Min. Max. Units SS↓ (select) to SCK↑ (initial) 500 — ns 11 SCK high 550 — ns 12 SCK low 550 — ns 10 Note 1: 13 SCK↓ (last) to SS↑ (deselect) 800 — ns 14 SDI setup before SCK↓ 100 — ns 15 SDI hold after SCK↓ 100 — ns 16 SDO valid after SCK↓ — 150 ns 17 SDO↑ rise — 50 ns 18 SDO↓ fall — 50 ns 19 SS↑ (deselect) to SDO High-z 10 50 ns Parameters are characterized, but not tested. 2009-2016 Microchip Technology Inc. DS40001393C-page 21 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 6.0 UART COMMUNICATIONS TABLE 6-1: UART HARDWARE INTERFACE AR1011 Pin Description M1 Connect M1 to VDD to select UART communications TX Transmit to host RX Receive from host SDO Connect SDO to VSS UART communication is fixed at 9600 baud rate, 8N1 format. Sleep mode will cause the TX line to drop low, which may appear as a 0x00 byte sent from the controller. DS40001393C-page 22 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 7.0 TOUCH REPORTING PROTOCOL Touch coordinates are sent from the controller to the host system in a 5-byte data packet, which contains the X-axis coordinate, Y-axis coordinate, and a “Pen-Up/ Down” touch status. The range for X-axis and Y-axis coordinates is from 04095 (12-bit). The realized resolution is 1024, and bits X1:X0 and Y1:Y0 are zeros. It is recommended that applications be developed to read the 12-bit coordinates from the packet and use them in a 12-bit format. This enhances the application robustness, as it will work with either 10 or 12 bits of coordinate information. The touch coordinate reporting protocol is shown below in Table 7-1. TABLE 7-1: TOUCH COORDINATE REPORTING PROTOCOL Byte # Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 1 1 R R R R R R P 2 0 X6 X65 X4 X3 X2 X1 X0 3 0 0 0 X11 X10 X9 X8 X7 4 0 Y6 Y5 Y4 Y3 Y2 Y1 Y0 5 0 0 0 Y11 Y10 Y9 Y8 Y7 where: • • • • P: 0 Pen Up, 1 Pen Down R: Reserved X11-X0: X-axis coordinate Y11-Y0: Y-axis coordinate 2009-2016 Microchip Technology Inc. DS40001393C-page 23 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 8.0 CONFIGURATION REGISTERS 8.1 • AR1010/AR1020 The Configuration registers allow application-specific customization of the controller. The default values have been optimized for most applications and are automatically used, unless you choose to change them. The factory default settings for the Configuration registers can be recovered by writing a value of 0xFF to address 0x00 of the EEPROM, then cycling power. • AR1011/AR1021 Unique sensors and/or product applications may benefit from adjustment of Configuration registers. Note: The factory default settings for the Configuration registers can be recovered by writing a value of 0xFF to addresses 0x01 and 0x29 of the EEPROM, then cycling power. Although most registers can be configured for a value ranging from 0 to 255, using a value outside the specified range for the specific register may negatively impact performance. TABLE 8-1: Restoring Default Parameters CONFIGURATION REGISTERS Register Name Address Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Offset AR1010/ AR1020 Default AR1011/ AR1021 Default 0x58 0x58 <Special Use> 0x00 <Non-Configurable> <Special Use> 0x01 <Non-Configurable> 0x01 0x01 TouchThreshold 0x02 Value of: 0-255 0xC5 0xC5 SensitivityFilter 0x03 Value of: 0-255 0x04 0x04 SamplingFast 0x04 Value of: 1, 2, 4, 8, 16, 32, 64, 128 0x04 0x04 SamplingSlow 0x05 Value of: 1, 2, 4, 8, 16, 32, 64, 128 0x10 0x10 AccuracyFilterFast 0x06 Value of: 1-8 0x02 0x04 AccuracyFilterSlow 0x07 Value of: 1-8 0x08 0x08 SpeedThreshold 0x08 Value of: 0-255 0x04 0x04 <Special Use> 0x09 <Non-Configurable> 0x23 0x23 SleepDelay 0x0A Value of: 0-255 0x64 0x64 PenUpDelay 0x0B Value of: 0-255 TouchMode 0x0C PD2 — PD1 PD0 PM1 PM0 PU2 — — — — — 0x80 0x80 PU0 0xB1 0xB1 48W CCE 0x00 0x00 0x19 0x19 PU1 TouchOptions 0x0D CalibrationInset 0x0E PenStateReportDelay 0x0F Value of: 0-40 0xC8 0xC8 <Special Use> 0x10 Value of: 0-255 0x03 0x03 TouchReportDelay 0x11 <Non-Configurable> 0x00 0x00 <Special Use> 0x12 Value of: 0-255 0x00 0x00 Configuration registers are defined as an Offset value from the Start address for the register group. To read or write to a register, do the following: • Issue the REGISTER_START_ADDRESS_REQUEST command to obtain the Start address for the register group. • Calculate the desired register’s absolute address by adding the register’s Offset value to Start address for the register group. DS40001393C-page 24 • Issue the REGISTER_READ or REGISTER_WRITE command, using the calculated register’s absolute address. Warning: Use of invalid register values will yield unpredictable results. 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 8.2 8.2.1 Register Descriptions TouchThreshold Register (OFFSET 0x02) The TouchThreshold register sets the threshold for a touch condition to be detected as a touch. A touch is detected if it is below the TouchThreshold setting. Too small of a value might prevent the controller from accepting a real touch, while too large of a value might allow the controller to accept very light or false touch conditions. Valid values are as follows: 0 ≤ TouchThreshold ≤ 255 8.2.2 SensitivityFilter Register (OFFSET 0x03) The SensitivityFilter register sets the level of touch sensitivity. A higher value is more sensitive to a touch (accepts a lighter touch), but may exhibit a less stable touch position. A lower value is less sensitive to a touch (requires a harder touch), but will provide a more stable touch position. Valid values are as follows: 0 ≤ SensitivityFilter ≤ 10 8.2.3 SamplingFast Register (OFFSET 0x04) The SamplingFast register sets the level of touch measurement sample averaging, when touch movement is determined to be fast. See the SpeedThreshold register for information on the touch movement threshold. A lower value will provide for a higher touch coordinate reporting rate when touch movement is fast, but may exhibit more high-frequency random noise error in the touch position. A higher value will reduce the touch coordinate reporting rate when touch movement is fast, but will reduce high-frequency random noise error in the touch position. Valid values are as follows: SamplingFast: <1, 4, 8, 16, 32, 64, 128> Recommended Values: <4, 8, 16> Higher values may improve accuracy with some sensors. 8.2.4 8.2.5 AccuracyFilterFast Register (OFFSET 0x06) The AccuracyFilterFast register sets the level of an accuracy enhancement filter, used when the touch movement is fast. See the SpeedThreshold register for information on the touch movement threshold. A lower value will provide better touch coordinate resolution when the touch motion is fast, but may exhibit more low-frequency noise error in the touch position. A higher value will reduce touch coordinate resolution when the touch motion is fast, but will reduce lowfrequency random noise error in the touch position. Valid values are as follows: 1 ≤ AccuracyFilterFast ≤ 8 Higher values may improve accuracy with some sensors. 8.2.6 AccuracyFilterSlow Register (OFFSET 0x07) The AccuracyFilterSlow register sets the level of an accuracy enhancement filter, used when the touch movement is slow. See the SpeedThreshold register for information on the touch movement threshold. A lower value will provide better touch coordinate resolution when the touch motion is slow, but may exhibit more low-frequency noise error in the touch position. A higher value will reduce touch coordinate resolution when the touch motion is slow, but will reduce lowfrequency random noise error in the touch position. Valid values are as follows: 1 ≤ AccuracyFilterSlow ≤ 8 8.2.7 SpeedThreshold Register (OFFSET 0x08) The SpeedThreshold register sets the threshold for touch movement to be considered as slow or fast. A lower value reduces the touch movement speed that will be considered as fast. A higher value increases the touch movement speed that will be considered as fast. Valid values are as follows: 0 ≤ SpeedThreshhold ≤ 255 SamplingSlow Register (OFFSET 0x05) The SamplingSlow register sets the level of touch measurement sample averaging, when touch movement is slow. See the SpeedThreshold register for information on the touch movement threshold. A lower value will increase the touch coordinate reporting rate when the touch motion is slow, but may exhibit a less stable more jittery touch position. A higher value will decrease the touch coordinate reporting rate when the touch motion is slow, but will provide a more stable touch position. Valid values are as follows: SamplingSlow: 1, 2, 4, 8, 16, 32, 64, 128 2009-2016 Microchip Technology Inc. DS40001393C-page 25 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 8.2.8 SleepDelay Register (OFFSET 0x0A) 8.2.10 TouchMode Register (OFFSET 0x0C) The SleepDelay register sets the time duration with no touch or command activity that will cause the controller to enter a low-power Sleep mode. Valid values are as follows: The TouchMode register configures the action taken for various touch states. 0 ≤ SleepDelay ≤ 255 Touch States: Sleep Delay Time = SleepDelay * 100 ms; when SleepDelay > 0 1. A value of zero disables the Sleep mode, such that the controller will never enter low-power Sleep mode. A touch event will wake the controller from low-power Sleep mode and start sending touch reports. Communications sent to the controller will wake it from the lowpower Sleep mode and initiate action to the command. 8.2.9 PenUpDelay Register (OFFSET 0x0B) The PenUpDelay register sets the duration of a pen-up event that the controller will allow, without sending a pen-up report for the event. The delay time is started upon detecting a pen-up condition. If a pen down is reestablished before the delay time expires, then pen-down reports will continue without a pen up being sent. This effectively debounces a touch event in process. There are three states of touch for the controller’s touch reporting action which can be independently controlled. Pen Down (initial touch) User defined 0-3 touch reports, with selectable pen states. 2. Pen Movement (touch movement after initial touch) User defined no-touch reports or streaming touch reports, with selectable pen states. 3. Pen Up (touch release) User defined 0-3 touch reports, with selectable pen states. Every touch report includes a “P” (Pen) bit that indicates the pen state. • Pen Down: P = 1 • Pen Up: P=0 A lower value will make the controller more responsive to pen ups, but will cause more touch drop outs with a lighter touch. A higher value will make the controller less responsive to pen ups, but will reduce the number of touch drop outs with a lighter touch. Valid values are as follows: 0 ≤ PenUpDelay ≤ 255 Pen-up Delay Time ≈ PenUpDelay * 240 μs DS40001393C-page 26 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER REGISTER 8-1: TouchMode REGISTER FORMAT R/W R/W R/W R/W R/W R/W R/W R/W PD2 PD1 PD0 PM1 PM0 PU2 PU1 PU0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ bit 7-5 PD<2:0>: Pen-Down State bits (action taken upon pen down). 000 = No touch report 001 = Touch report with P=0 010 = Touch report with P=1 011 = Touch report with P=1, then touch report with P=0 100 = Touch report with P=0, then touch report with P=1, then touch report with P=0 101 = Touch report with P=0, then touch report with P=1 bit 4-3 PM<1:0>: Pen Movement State bits (action taken upon pen movement). 00 = No touch report 01 = Touch report with P=0 10 = Touch report with P=1 bit 2-0 PU<2:0>: Pen-Up State bits (action taken upon pen up). 000 = No touch report 001 = Touch report with P=0 010 = Touch report with P=1 011 = Touch report with P=1, then touch report with P=0 100 = Touch report with P=0, then touch report with P=1, then touch report with P=0 101 = Touch report with P=0, then touch report with P=1 A couple of typical setup examples for the TouchMode are as follows: • Report a pen down P=1 on initial touch, followed by reporting a stream of pen downs P=1 during the touch, followed by a final pen up P=0 on touch release. TouchMode = 0b01010001 = 0x51 • Report a pen up P=0 then a pen down P=1 on initial touch, followed by reporting a stream of pen downs P=1 during the touch, followed by a final pen up P=0 on touch release. TouchMode = 0b10110001 = 0xB1 2009-2016 Microchip Technology Inc. DS40001393C-page 27 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 8.2.11 TouchOptions Register (OFFSET 0x0D) The TouchOptions register contains various “touch” related option bits. REGISTER 8-2: TouchOptions REGISTER U-0 U-0 U-0 U-0 U-0 U-0 R/W R/W — — — — — — 48W CCE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ bit 7-2 Unimplemented: Read as ‘0’ bit 1 48W: 4-Wire or 8-Wire Sensor Selection bit 1 = Selects 8-wire Sensor Operating mode 0 = Selects 4-wire Sensor Operating mode bit 0 CCE: Calibrated Coordinates Enable bit 1 = Enables calibrated coordinates, if the controller has been calibrated 0 = Disables calibrated coordinates Note: A 4-wire touch sensor will not work if the 48W Configuration bit is incorrectly defined as 1, which selects 8-wire. An 8-wire touch sensor will provide basic operation if the 48W Configuration bit is incorrectly defined as 0, which selects 4wire. However, the benefit of the 8-wire sensor will only be realized if the 48W Configuration bit is correctly defined as 1, selecting 8-wire. 8.2.12 CalibrationInset Register (OFFSET 0x0E) The CalibrationInset register defines the expected position of the calibration points, inset from the perimeter of the touch sensor’s active area, by a percentage of the full scale dimension. This allows for the calibration targets to be placed inset from edge to make it easier for a user to touch them. Calibration Inset = (CalibrationInset/2) %, Range of 020% with 0.5% resolution For example, CalibrationInset = 25 (0x19) yields a calibration inset of (25/2) or 12.5%. During the calibration procedure, the controller will internally extrapolate the calibration point touch values in Calibration mode by 12.5% to achieve full scale. FIGURE 8-1: CALIBRATION TARGET EXAMPLE 12.5% of Full Scale Location of Calibration Targets presented during Calibration. 12.5% of Full Scale The CalibrationInset register value is only used when the CALIBRATION_MODE command is issued to the controller. In Calibration mode, the controller will extrapolate the calibration point touch report values by the defined CalibrationInset percentage to achieve full scale. A software application that issues the CALIBRATION_MODE command must present the displayed calibration targets at the same inset percentage as defined in this CalibrationInset register. Valid values are as follows: 0 ≤ CalibrationInset ≤ 40 DS40001393C-page 28 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 8.2.13 PenStateReportDelay Register (OFFSET 0x0F) The PenStateReportDelay register sets the delay time between sending of sequential touch reports for the “Pen-Down” and “Pen-Up” Touch mode states. See Section 8.2.10 “TouchMode Register (offset 0x0C)” for touch modes. For example, if “Pen-Up” state of the TouchMode register is configured to send a touch report with P=1, followed by a touch report with P=0, then this delay occurs between the two touch reports. This provides some timing flexibility between the two touch reports that may be desired in certain applications. Valid values are as follows. 0 ≤ PenStateReportDelay ≤ 255 Pen State Report Delay Time = PenStateReportDelay * 50 μs 8.2.14 TouchReportDelay Register (OFFSET 0x11) The TouchReportDelay register sets a forced delay time between successive touch report packets. This allows slowing down of the touch report rate, if desirable for a given application. For example, a given application may not need a high rate of touch reports and may want to reduce the overhead used to service all of the touch reports being sent. In this situation, increasing the value of this register will reduce the rate at which the controller sends touch reports. Valid values are as follows: 0 ≤ TouchReportDelay ≤ 255 Touch Report Delay Time ≈ TouchReportDelay * 500 μs 2009-2016 Microchip Technology Inc. DS40001393C-page 29 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.0 COMMANDS 9.1 Sending Commands 9.1.1 COMMAND SEND FORMAT The controller supports application-specific configuration commands as shown in Table 9-1, below. TABLE 9-1: COMMAND SEND FORMAT Byte # Name Value Description 1 Header 0x55 Header (mark beginning of command packet) 2 Size 0x<> Size, # of bytes following this byte 3 Command 0x<> Command ID 4 Data 0x<> Data, if applicable for the command : Data 0x<> Data, if applicable for the command To ensure command communication is not interrupted by touch activity, it is recommended that the controller touch is disabled, prior to other commands. This can be done as follows: 1. 2. 3. 4. Send DISABLE_TOUCH command Wait 50 ms Send desired commands Send ENABLE_TOUCH command 9.1.2 COMMAND RESPONSE A received command will be responded to as seen in Table 9-2 below. TABLE 9-2: COMMAND RESPONSE FORMAT Byte # Name Value Description 1 Header 0x55 2 Size 0x<> Size, # of bytes following this byte 3 Status 0x<> Status 4 Command 0x<> Command ID 5 Data 0x<> Data, if applicable for the command : Data 0x<> Data, if applicable for the command Header (mark beginning of command packet) The “Status” value within the response packet should be one of the following (See Table 9-3): TABLE 9-3: COMMAND RESPONSE STATUS VALUES Status Value Description 0x00 Success 0x01 Command Unrecognized 0x03 Header Unrecognized 0x04 Command Time Out (exceeded ~100 ms) 0xFC Cancel Calibration mode DS40001393C-page 30 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.1.3 DISABLE TOUCH BEFORE SENDING SUBSEQUENT COMMANDS The AR1000 does not support full duplex communications. It cannot send touch reports to the host simultaneously with receiving commands from the host. Disable AR1000 touch reporting prior to sending any other command(s), then re-enable touch reporting when complete with executing other commands. 1. Send the DISABLE_TOUCH command. Check for expected command response. 2. Send a desired command. 3. Repeat at step 2 if another command is to be sent. Send the ENABLE_TOUCH command. Check for expected command response. 4. Check for expected command response. 9.1.4 CONFIRM COMMAND IS SENT Confirm each command sent to the AR1000, prior to issuing another command, to ensure it is executed. This is accomplished by evaluating the AR1000 response to a command that has been sent to it. Check for each of the following five conditions to be met (See Table 9-4). TABLE 9-4: COMMAND RESPONSE ERROR CONDITIONS Condition Response Byte Description Header 1 Header 0x55 value is expected Size 2 Size 0x<> value to match what is expected for command sent Status 3 Status 0x00 “success” value is expected ID 4 Command ID 0x<> value to match what is expected (ID of sent command) Data 5 to end Data byte count to match what is expected for command sent 0x<> represents a value that is dependent on the command. An error has occurred if no response is received at all or if any of the above conditions are not met in the response from the AR1000. If an error condition occurs, delay for a period of ~50 ms then send the same command again. 2009-2016 Microchip Technology Inc. DS40001393C-page 31 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.2 AR1000 Commands TABLE 9-5: COMMAND SET SUMMARY Command Value Command Description 0x10 GET_VERSION 0x12 ENABLE_TOUCH 0x13 DISABLE_TOUCH 0x14 CALIBRATE_MODE 0x20 REGISTER_READ 0x21 REGISTER_WRITE 0x22 REGISTER_START_ADDRESS_REQUEST 0x23 REGISTERS_WRITE_TO_EEPROM 0x28 EEPROM_READ 0x29 EEPROM_WRITE 0x2B EEPROM_WRITE_TO_REGISTERS 9.3 AR1000 Command Descriptions 9.3.1 GET_VERSION – 0x10 Controller will return version number and type. Send: <0x55><0x01><0x10> Receive: <0x55><0x05><Response><0x10><Version High><Version Low><Type> where <Type> REGISTER 9-1: GET_VERSION <TYPE> FORMAT R/W R/W R/W R/W R/W R/W R/W R/W RS1 RS0 TP5 TP4 TP3 TP2 TP1 TP0 bit 7 bit 0 Legend: R = Readable bit bit 7-6 W = Writable bit U = Unimplemented bit, read as ‘0’ RS<1:0>: Resolution of Touch Coordinates bits 00 = 8-bit 01 = 10-bit 10 = 12-bit bit 5-0 TP<5:0>: Type of Controller bits 001010 = ARA10 DS40001393C-page 32 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.3.2 ENABLE_TOUCH – 0x12 Controller will send touch coordinate reports for valid touch conditions. Send: <0x55><0x01><0x12> Receive: <0x55><0x02><Response><0x12> 9.3.3 DISABLE_TOUCH – 0x13 Controller will not send any touch coordinate reports. A touch will, however, still wake-up the controller if asleep. Send: <0x55><0x01><0x13> Receive: <0x55><0x02><Response><0x13> 9.3.4 CALIBRATE – 0x14 Enter Calibration mode. This instructs the controller to enter a mode of accepting the next four touches as the calibration point coordinates. See Section 10.1 “Calibration of Touch Sensor with Controller” for an example. Completion of Calibration mode will automatically store the calibration point coordinates in on-board controller memory and set (to 1) the CCE bit of the TouchOptions register. This bit enables the controller to report touch coordinates that have been processed with the previously collected calibration data. To provide for proper touch orientation, the four sequential calibration touches must be input in the physical order on the touch sensor, as shown in Figure 9-1. FIGURE 9-1: CALIBRATION ROUTINE SEQUENCE #1 Upper Left #2 Upper Right Touch Sensor #4 Lower Left #3 Lower Right Upon completion, the controller’s register values and calibration data are stored to the EEPROM. The Calibration mode will be canceled by sending any command before the mode has been completed. If the calibration is canceled, the controller response may appear incorrect or incomplete. This is expected behavior. 2009-2016 Microchip Technology Inc. DS40001393C-page 33 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.3.4.1 Send: AR1010/AR1020 Calibrate Response <0x55><0x02><0x14><Calibration Type> Calibration Type Description 0x04 4 point Receive: <0x55><0x02><0x00><0x14> for initial command response <0x55><0x02><0x00><0x14> Response for touch of Calibration point #1 <0x55><0x02><0x00><0x14> Response for touch of Calibration point #2 <0x55><0x02><0x00><0x14> Response for touch of Calibration point #3 <0x55><0x02><0x00><0x14> Response for touch of Calibration point #4 A successful CALIBRATE command results in five response packets being sent to the host. Once the response has been received for the completed 4th target, a delay of one second must be implemented prior to sending any commands to the controller. This one second delay insures all data has been completely written to the EEPROM. 9.3.4.2 Send: AR1011/AR1021 Calibrate Response <0x55><0x02><0x14><Calibration Type> Calibration Type Description 0x04 4 point Receive: <0x55><0x02><0x00><0x14> for initial command response <0x55><0x02><0x00><0x14> Response for touch of Calibration point #1 <0x55><0x02><0x00><0x14> Response for touch of Calibration point #2 <0x55><0x02><0x00><0x14> Response for touch of Calibration point #3 <0x55><0x02><0x00><0x14> Response for touch of Calibration point #4 <0x55><0x02><0x00><0x14> Response after EEPROM has been written A successful CALIBRATE command results in six response packets being sent to the host. DS40001393C-page 34 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.3.4.3 Calibration Data Encoded and Stored in EEPROM The raw touch coordinates, decoded by the controller, for each of the four calibration touches are extrapolated if CalibrationInset was non-zero. The four coordinate pairs are then re-oriented, if required, such that the upper left corner is the minimum (X,Y) “origin” value pair and the lower right corner is the maximum (X,Y) value pair. System integrators may prefer to preload a calibration into their design. This allows the user to properly navigate to the calibration routine icon or shortcut without the use of a mouse. This also addresses the need to calibrate each system individually before deploying it to the field. Separator Coordinates are 10-bit significant values, scaled to 16-bit and stored in a High (Hi) and Low (Lo) byte pair. Upper Left (Node 1) Upper Right (Node 2) Lower Right (Node 3) X Lo Y Hi Lo X Hi Lo Y Hi Lo X Hi Lo Lower Left (Node 4) Y Hi Lo X Hi Lo Flip State Y Hi Lo Hi Decode the above data to as follows: 1. 2. 3. Swap the order of stored low and high bytes for a given coordinate. Convert the 16-bit value (stored high and low bytes) from hexadecimal to decimal. Divide the result by 64 to properly rescale the 16-bit stored value back to a 10-bit significant coordinate. Example of Low = 0x40 and High = 0xF3: Swap: 0xF340 Hex to Decimal: 62272 Divide by 64: 973 REGISTER 9-2: FLIP STATE BYTE U-0 U-0 U-0 U-0 U-0 R/W R/W R/W — — — — — XYFLIP XFLIP YFLIP bit 7 bit 0 Legend: R = Readable bit W = Writable bit bit 7-3 Unimplemented: Read as ‘0’ bit 2 XYFLIP: X and Y Axis Flip bit 1 = X and Y axis are flipped 0 = X an Y axis are not flipped bit 1 XFLIP: X-Axis Flip bit 1 = X-axis flipped 0 = X-axis not flipped bit 0 YFLIP:Y-Axis Flip bit 1 = Y-axis flipped 0 = Y-axis not flipped U = Unimplemented bit, read as ‘0’ For storing desired calibration values to the EEPROM: • AR1010/AR1020 (See Section 9.3.12 “EEPROM Map”). • AR1011/AR1021 (See Section 9.3.12 “EEPROM Map” and Section 10.2 “AR1011/AR1021 Storing Default Calibration Values to EEPROM”). 2009-2016 Microchip Technology Inc. DS40001393C-page 35 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.3.5 REGISTER_READ – 0x20 Reads a value from a controller register location. This can be used to determine a controller configuration setting. Configuration registers are defined as an Offset value from the Start address for the register group. Read a register as follows: 1. 2. 3. Issue the REGISTER_START_ADDRESS_REQUEST command to obtain the Start address for the register group. Calculate the desired register’s absolute address by adding the register’s Offset value to Start address for the register group. Issue this REGISTER_READ command, as follows, using the calculated register’s absolute address: Send: <0x55><0x04><0x20><Register Address High byte><Register Address Low byte><# of Registers to Read> The AR1000 controller will ignore the value entered for the Register Address High Byte. However, 0x00 is recommended to safeguard against any possible future product development. 9.3.7 REGISTER_START_ADDRESS_REQUEST – 0x22 Configuration registers are defined as an Offset value from the Start address for the register group. This command returns the Start address for the register group. Send: <0x55><0x01><0x22> Receive: <0x55><0x03><Response><0x22><Regi ster Start Address> 9.3.8 REGISTERS_WRITE_TO_EEPROM – 0x23 Register Address High byte: 0x00 Save Configuration register values to EEPROM. This allows the controller to remember configurations settings through controller power cycles. # of Registers to Read: Send: 0x01 thru 0x08 <0x55><0x01><0x23> Receive: <0x55><0x02 + # of Registers Read><Response><0x20><Register value>…<Register value> Receive: <0x55><0x02><Response><0x23> The AR1000 controller will ignore the value entered for the Register Address High Byte. However, 0x00 is recommended to safeguard against any possible future product development. The controller has 256 bytes of on-board EEPROM. 9.3.6 REGISTER_WRITE – 0x21 Write a value to a controller register location. This can be used to change a controller configuration setting. Configuration registers are defined as an Offset value from the Start address for the register group. Write a register as follows: 1. 2. 3. Issue the REGISTER_START_ADDRESS_REQUEST command to obtain the Start address for the register group. Calculate the desired register’s absolute address by adding the register’s Offset value to Start address for the register group. Issue this REGISTER_WRITE command, as follows, using the calculated register’s absolute address: Send: <0x55><0x04 + # Registers to Write><0x21><Register Address High byte><Register Address Low byte> <# of Registers Write><Data>…<Data> 9.3.9 EEPROM_READ – 0X28 • The first 128 bytes (address range 0x00-0x7F) are reserved by the controller for the Configuration register settings and calibration data. • The second 128 bytes (address range 0x80-0xFF) are provided for the user’s application, if desired. This command provides a means to read values from the EEPROM. Send: <0x55><0x04><0x28><EEPROM Address High byte><EEPROM Address Low byte><# of EEPROM to Read> Register Address High byte: 0x00 # of Registers to Read: 0x01 thru 0x08 Receive: <0x55><0x02 + # EEPROM Read><Response><0x28><EEPROM value>…<EEPROM value> The AR1000 controller will ignore the value entered for the EEPROM Address High Byte. However, 0x00 is recommended to safeguard against any possible future product development. to Register Address High byte: 0x00 # of Registers to Read: 0x01 thru 0x08 Receive: <0x55><0x02><Response><0x21> DS40001393C-page 36 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 9.3.10 EEPROM_WRITE – 0x29 9.3.12 The controller has 256 bytes of on-board EEPROM. This command provides a means to write values to the user space within the EEPROM. • The first 128 bytes (address range 0x00-0x7F) are reserved by the controller for the Configuration register settings and calibration data. Only the Register Write to EEPROM command should be used to write Configuration registers to EEPROM. Failure to use the Register Write command to save Configuration registers to EEPROM may result in failures or reverting to previously stored Configuration register values. • The second 128 bytes (address range 0x80-0xFF) are provided for the user’s application, if desired. EEPROM MAP The first 128 bytes in address range 0x00:0x7F are reserved by the controller for the Configuration register settings and calibration data. The mapping of data in this reserved controller space of the EEPROM may change over different revisions within the product lifetime. The EEPROM_WRITE command must not be used to write directly to the lower 128 bytes of the controller EEPROM space of 0x00:0x7F. The second 128 bytes in address range 0x80:0xFF are provided for the user’s application, if desired. TABLE 9-6: AR1010/AR1020 EEPROM AND REGISTER MAP EEPROM Address Function Warning: ONLY write to user EEPROM addresses of 0x80-0xFF. 0x00 <Special Use> 0x01 <Special Use> One of the following actions is required for EEPROM changes to be used by the controller: 0x02 <Special Use> 0x03 Touch Threshold • The controller power must be cycled from OFF to ON or • Issue the EEPROM_WRITE_TO_REGISTERS command. 0x04 Sensitivity Filter 0x05 Sampling Fast 0x06 Sampling Slow 0x07 Accuracy Filter Fast Write to EEPROM as follows: 0x08 Accuracy Filter Slow Send: <0x55><0x04 + # EEPROM to Write><0x29><EEPROM Address High byte><EEPROM Address Low byte> 0x09 Speed Threshold 0x0A <Special Use> 0x0B Sleep Delay 0x0C Pen-Up Delay 0x0D Touch Mode <# of EEPROM Write><Data>…<Data> to Register Address High byte: 0x00 0x0E Touch Options # of Registers to Read: 0x01 thru 0x08 0x0F Calibration Inset Receive: <0x55><0x02><Response><0x29> 0x10 Pen State Report Delay The AR1000 controller will ignore the value entered for the EEPROM Address High Byte. However, 0x00 is recommended to safeguard against any possible future product development. 0x11 <Reserved> 0x12 Touch Report Delay 0x13 <Special Use> 0x14 Data Block Separator 0x15 Calibration UL X-low 0x16 Calibration UL X-high 0x17 Calibration UL Y-low 0x18 Calibration UL Y-high 0x19 Calibration UR X-low 0x1A Calibration UR X-high 0x1B Calibration UR Y-low 0x1C Calibration UR Y-high 0x1D Calibration LR X-low 0x1E Calibration LR X-high 0x1F Calibration LR Y-low 9.3.11 EEPROM_WRITE_TO_REGISTERS – 0x2B Write applicable EEPROM data to Configuration registers. This will cause the controller to immediately begin using changes made to EEPROM stored Configuration register values. A power cycle of the controller will automatically cause the controller to use changes made to the EEPROM stored Configuration register values, without the need for issuing this command. This command eliminates the need for the power cycle. Send: <0x55><0x01><0x2B> Receive: <0x55><0x02><Response><0x2B> 2009-2016 Microchip Technology Inc. DS40001393C-page 37 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER TABLE 9-6: AR1010/AR1020 EEPROM AND REGISTER MAP TABLE 9-7: AR1011/AR1021 EEPROM AND REGISTER MAP EEPROM Address Function EEPROM Address Function 0x20 Calibration LR Y-high 0x1D Calibration UR Y-low 0x21 Calibration LL X-low 0x1E Calibration UR Y-high 0x22 Calibration LL X-high 0x1F Calibration LR X-low 0x23 Calibration LL Y-low 0x20 Calibration LR X-high 0x24 Calibration LL Y-high 0x21 Calibration LR Y-low 0x25 Calibration Flip State 0x22 Calibration LR Y-high 0x26:0x7E <Special Use> 0x23 Calibration LL X-low 0x7F End of Controller Space 0x24 Calibration LL X-high 0x80:0xFF User Space 0x25 Calibration LL Y-low 0x26 Calibration LL Y-high 0x27 Calibration Flip State TABLE 9-7: AR1011/AR1021 EEPROM AND REGISTER MAP 0x28 Calibration – Checksum 0x29:0x50 <Special Use> Not used 0x51:0x7F <Reserved> 0x01 Configuration Registers – Block Key 0x80:0xFF User Space 0x02 <Special Use> EEPROM Address Function 0x00 0x03 <Special Use> 0x04 Touch Threshold 0x05 Sensitivity Filter 0x06 Sampling Fast 0x07 Sampling Slow 0x08 Accuracy Filter Fast 0x09 Accuracy Filter Slow 0x0A Speed Threshold 0x0B <Special Use> 0x0C Sleep Delay 0x0D Pen-Up Delay 0x0E Touch Mode 0x0F Touch Options 0x10 Calibration Inset 0x11 Pen State Report Delay 0x12 <Special Use> 0x13 Touch Report Delay 0x14 <Special Use> 0x15 Configuration Registers – Checksum 0x16 Calibration - Block Key 0x17 Calibration UL X-low 0x18 Calibration UL X-high 0x19 Calibration UL Y-low 0x1A Calibration UL Y-high 0x1B Calibration UR X-low 0x1C Calibration UR X-high DS40001393C-page 38 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 10.0 APPLICATION NOTES 5. 10.1 Calibration of Touch Sensor with Controller Send:<0x55><0x05><0x21><0x00><0x2E><0x01 ><0x19> The reported coordinates from a touch screen controller are typically calibrated to the application’s video display. The task is often left up to the host to perform. This controller provides a feature for it to send coordinates that have already been calibrated, rather than the host needing to perform this task. If enabled, the feature will apply pre-collected 4-point calibration data to the reported touch coordinates. Calibration only accounts for X and Y directional scaling. It does not correct for angular errors due to rotation of the touch sensor on the video display. Set the Calibration Inset by writing the desired value to the CalibrationInset register. Receive: <0x55><0x02><0x00><0x21> 6. Issue the CALIBRATE_MODE command. Send: <0x55><0x02><0x14><0x04> Receive: <0x55><0x02><0x00><0x14> 7. Software must display the first calibration point target in the upper left quadrant of the display and prompt the user to touch and release the target. FIGURE 10-1: The calibration process can be canceled at anytime by sending a command to the controller. Upon completion of the calibration process, the calibration data is automatically stored to the EEPROM and “Calibrated Coordinates” is enabled. Touch and The process of “calibration” with the controller is described below. 1. Release Target Disable touch reporting by issuing <Disable Touch> command. Send: 8. <0x55><0x01><0x13> Receive: <0x55><0x02><Response><0x13> 2. Get register group Start address by issuing REGISTER_START_ADDRESS_REQUEST command. A register Start address of 0x20 is used below, for this example. Send: 9. Wait for the user to touch and release the first calibration point target. Do this by looking for a controller response of: <0x55><0x02><0x00> <0x14> Software must display the second calibration point target in the upper right quadrant of the display and prompt the user to touch and release the target. <0x55><0x01><0x22> Receive: <0x55><0x03><0x00><0x22><0x20> 3. SUGGESTED TEXT FOR FIRST CALIBRATION TARGET Calculate the CalibrationInset register’s address by adding its offset value of 0x0E to the register group Start address of 0x20. FIGURE 10-2: SUGGESTED TEXT FOR SECOND CALIBRATION TARGET Register Address = Register Start Address + CalibratioInset Register Offset = 0x20 + 0x0E = 0x2E Touch and 4. Release Target Calculate the desired CalibrationInset register. value for the A Calibration Inset of 12.5% is used below for this example. CalibrationInset = 2 * Desire Calibration Inset % = 2 * 12.5 = 25 = 0x19 2009-2016 Microchip Technology Inc. 10. Wait for the user to touch and release the second calibration point target. Do this by looking for a controller response of: <0x55><0x02><0x00><0x14> DS40001393C-page 39 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 11. Software must display the third calibration point target in the lower right quadrant of the display and prompt the user to touch and release the target. FIGURE 10-3: SUGGESTED TEXT FOR THIRD CALIBRATION TARGET Touch and Release Target 14. Wait for the user to touch and release the fourth calibration point target. Do this by looking for a controller response of: <0x55><0x02><0x00><0x14> 15. Wait for the controller to correctly write calibration data into EEPROM • AR1010/AR1020: Wait one second for data to be stored into EEPROM • AR1011/AR1021: Wait for a controller response of <0x55><0x02><0x00><0x14> 16. Enable touch reporting by issuing ENABLE_TOUCH command. Send: <0x55><0x01><0x12> Receive: <0x55><0x02><Response><0x12> 12. Wait for the user to touch and release the third calibration point target. Do this by looking for a controller response of: <0x55><0x02><0x00><0x14> 13. Software must display the fourth calibration point target in the lower left quadrant of the display and prompt the user to touch and release the target. FIGURE 10-4: SUGGESTED TEXT FOR FOURTH CALIBRATION TARGET Touch and Release Target DS40001393C-page 40 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 10.2 An example of calculating the checksum is shown below (See Table 10-1). AR1011/AR1021 Storing Default Calibration Values to EEPROM If you wish to implement fixed calibration values, preloaded into the AR1000 EEPROM, then the following procedure must be followed (See Section 10.2.1 “Preparation for Fixed Calibration Values”). 10.2.1 PREPARATION FOR FIXED CALIBRATION VALUES Determine if fixed calibration values are suitable for your application and determine your desired values. Calculate a checksum for your custom data set. See Section 9.3.4.3 “Calibration Data Encoded and Stored in EEPROM” for additional details regarding calibration data format. TABLE 10-1: CHECKSUM CALCULATION EXAMPLE Description Value Operation Checksum Result Seed 0x45 n/a 0x45 Block Key 0x55 0x45 + 0x55 = 0x9A Upper Left X Low byte 0x06 0x9A + 0x06 = 0xA0 Upper Left X High byte 0x1B 0xA0 + 0x1B = 0xBB Upper Left Y Low byte 0xA5 0xBB + 0xA5 = 0x60 Upper Left Y High byte 0x08 0x60 + 0x08 = 0x68 Upper Right X Low byte 0x13 0x68 + 0x13 = 0x7B Upper Right X High byte 0xDF 0x7B + 0xDF = 0x5A Upper Right Y Low byte 0xF4 0x5A + 0xF4 = 0x4E Upper Right Y High byte 0x0B 0x4E + 0x0B = 0x59 Lower Right X Low byte 0x98 0x59 + 0x98 = 0xF1 Lower Right X High byte 0xE4 0xF1 + 0xE4 = 0xD5 Lower Right Y Low byte 0x1E 0xD5 + 0x1E = 0xF3 Lower Right Y High byte 0xEC 0xF3 + 0xEC = 0xDF Lower Left X Low byte 0xBF 0xDF + 0xBF = 0x9E Lower Left X High byte 0x1A 0x9E + 0x1A = 0xB8 Lower Left Y Low byte 0x32 0xB8 + 0x32 = 0xEA Lower Left Y High byte 0xE7 0xEA + 0xE7 = 0xD1 0x01 0xD1 + 0x01 = Flip State Checksum 0xD2 0xD2 The Checksum is an 8-bit value calculated by successive additions with overflow ignored, as shown below. Checksum = 0x45 For each of the 18 calibration values, starting at the Block Key and ending with the Flip State Checksum += Calibration value Next Calibration value 2009-2016 Microchip Technology Inc. DS40001393C-page 41 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 10.2.2 EXECUTION OF FIXED CALIBRATION VALUE LOADING Follow error checking practices by checking the AR1000 responses to issued commands. 1. 2. 3. 4. Send the AR1000 DISABLE_TOUCH command. Use the AR1000 EEPROM_WRITE command multiple times to write the following to the AR1000 EEPROM. a. Block Key 0x55 to address 0x16 b. Data set to addresses 0x17:0x27. See Section 9.3.4.3 “Calibration Data Encoded and Stored in EEPROM” and Section 9.3.12 “EEPROM Map”. c. Checksum for the data block to address 0x28 d. Mirror image of a, b and c from above to address 0x3E:0x50 Set the CCE bit of the TouchOptions register. This will enable the controller to use the calibration data on the next power boot. See Section 10.2.3 “Configuring the CCE bit to Use Fixed Calibration Values” for additional details on the CCE bit. Send the AR1000 ENABLE_TOUCH (0x12) command. 10.2.3 CONFIGURING THE CCE BIT TO USE FIXED CALIBRATION VALUES The CCE bit of the TouchOptions Register (offset 0x0D) must be set to ‘1’ to enable the usage of the stored calibration values in EEPROM. This should be completed before re-enabling the controller via the ENABLE_TOUCH command. REGISTER 10-1: CCE BIT FORMAT U-0 U-0 U-0 U-0 U-0 U-0 R/W R/W — — — — — — 48W CCE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ bit 7-2 Unimplemented: Read as ‘0’ bit 1 48W: 4-Wire or 8-Wire Sensor Selection bit 1 = Selects 8-wire Sensor Operating mode 0 = Selects 4-wire Sensor Operating mode bit 0 CCE: Calibrated Coordinates Enable bit 1 = Enables calibrated coordinates, if the controller has been calibrated 0 = Disables calibrated coordinates DS40001393C-page 42 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 1. 2. 3. 4. 5. Send the DISABLE_TOUCH (0x13) command. Send the REGISTER_START_ADDRESS_REQUEST (0x22) to determine the absolute address for TouchOptions Register. Send the REGISTER_WRITE (0x21) command to set the CCE bit of the TouchOptions Register. Send REGISTERS_WRITE_TO_EEPROM (0x23) command to have all current registers stored into EEPROM. Send the AR1000 ENABLE_TOUCH (0x12) command. The controller will use the stored calibration data after cycling power to the controller. 10.2.4 EEPROM_WRITE COMMAND TO STORE DEFAULT CALIBRATION The EEPROM_WRITE command is shown in this section. See Section 9.0 “Commands” for more command details. 10.2.5 QUALITY TEST Although not required, a level of quality assurance can be added to the process by the application issuing multiple EEPROM_READ commands to the AR1000. The response data from the EEPROM_READ commands would be tested by the application against the application’s desired data as a quality check. 10.2.6 EXAMPLE COMMAND SEQUENCE An example eight command sequence for the entire process is shown below. All values shown are in hexadecimal. Calibration values are applications specific and have been symbolically represented as follows: ULxL = Upper Left corner x-coordinate Low byte : LLyH = Lower Left corner y-coordinate High byte DISABLE_TOUCH <> = application specific value Send to AR1000: 0x55 Header 0x<> Number of bytes to follow this one 0x29 Command ID 0x00 Desired EEPROM address to write high byte. Always 0x00 0x<> Desired EEPROM address to write low byte 0x<> Number of consecutive EEPROM addresses to write (supports 0x01 to 0x08) 0x<> Value # 1 to write 0x<> Value # 2 to write, if applicable 0x<> Value # 3 to write, if applicable 0x<> Value # 4 to write, if applicable 0x<> Value # 5 to write, if applicable 0x<> Value # 6 to write, if applicable 0x<> Value # 7 to write, if applicable 0x<> Value # 8 to write, if applicable Response from AR1000: 0x55 Header 0x02 Number of bytes to follow this one 0x00 Success response 0x29 Command ID 2009-2016 Microchip Technology Inc. DS40001393C-page 43 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER Disable Touch Command: 55 01 13 Response: 55 02 00 13 Write Calibration to EEPROM Image # 1 Command: 55 0C 29 00 Response: 55 02 00 29 Command: 55 0C 29 00 Response: 55 02 00 29 Command: 55 07 29 00 Response: 55 02 00 29 16 08 55 ULxL ULxH ULyL ULyH URxL URxH URyL 1E 08 URyH LRxL LRxH LRyL LRyH LLxL 26 03 LLyH FlipS Chksm 3E 08 55 ULxL ULxH ULyL ULyH URxL URxH URyL 46 08 URyH LRxL LRxH LRyL LRyH LLxL 4E 03 LLyH FlipS Chksm LLxH LLyL Write Calibration to EEPROM Image # 2 Command: 55 0C 29 00 Response: 55 02 00 29 Command: 55 0C 29 00 Response: 55 02 00 29 Command: 55 07 29 00 Response: 55 02 00 29 LLxH LLyL Enable Use of Calibrated Data Command: 55 01 22 Response: 55 03 00 22 <Start Address> Command: 4/8-Wire 55 05 21 00 <Start Address + 0x0D> 01 01 5-Wire 55 05 21 00 <Start Address + 0x0D> 01 03 Response: 55 02 00 21 Command: 55 01 12 Response: 55 02 00 Enable Touch DS40001393C-page 44 12 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 11.0 ELECTRICAL SPECIFICATIONS Absolute Maximum Ratings(†) Ambient temperature under bias....................................................................................................... -40°C to +125°C Storage temperature ........................................................................................................................ -65°C to +150°C Voltage on VDD with respect to VSS .................................................................................................... -0.3V to +6.5V Voltage on all other pins with respect to VSS ........................................................................... -0.3V to (VDD + 0.3V) Total power dissipation................................................................................................................................... 800 mW Maximum current out of VSS pin .................................................................................................................... 300 mA Maximum current into VDD pin ....................................................................................................................... 250 mA Input clamp current (VI < 0 or VI > VDD) 20 mA Maximum output current sunk by any I/O pin.................................................................................................... 25 mA Maximum output current sourced by any I/O pin .............................................................................................. 25 mA † NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. † NOTICE: This device is sensitive to ESD damage and must be handled appropriately. Failure to properly handle and protect the device in an application may cause partial to complete failure of the device. 2009-2016 Microchip Technology Inc. DS40001393C-page 45 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 11.1 Minimum Operating Voltage The AR1000 series controller will operate down to 2.5V ± 5%. Touch performance will be optimized by using the highest allowable voltage for the design. The PICkit™ Serial included in the AR1000 Development kit supports 3V-5V range of operation. 11.2 AR1000 Electrical Characteristics Operating Voltage: 2.5 ≤ VDD ≤ 5.25V Function Pin Input M1 M1 VSS ≤ VIL ≤ 0.15*VDD (0.25*VDD + 0.9V) ≤ VIH ≤ VDD — M2 M2 VSS ≤ VIL ≤ 0.15*VDD (0.25*VDD + 0.9V) ≤ VIH ≤ VDD — SCL/SCK SCL/SCK/TX VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD — TX SCL/SCK/TX — VSS ≤ VOL(1) ≤ (1.2V – 0.15*VDD)(2) (1.25*VDD – 2.25V)(3) ≤ VOH(1) ≤ VDD SDI SDI/SDA/RX VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD — SDO SDO — VSS ≤ VOL(1) ≤ (1.2V – 0.15*VDD)(2) (1.25*VDD – 2.25V)(3) ≤ VOH(1) ≤ VDD SIQ SIQ — VSS ≤ VOL(1) ≤ (1.2V – 0.15*VDD)(2) (1.25*VDD – 2.25V)(3) ≤ VOH(1) ≤ VDD SDA SDI/SDA/RX VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD Open-drain RX SDI/SDA/RX VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD — SS SS VSS ≤ VIL ≤ 0.2*VDD 0.8*VDD ≤ VIH ≤ VDD — Note 1: 2: 3: Output These parameters are characterized but not tested. At 10 mA. At -4 mA. DS40001393C-page 46 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 12.0 PACKAGING INFORMATION 12.1 Package Marking Information 20-Lead SSOP (5.30 mm) Example AR1021 I/SS e3 1042256 20-Lead SOIC (7.50 mm) XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX YYWWNNN Legend: XX...X Y YY WW NNN e3 * Note: * Example AR1021 I/SO e3 1042256 Customer-specific information Year code (last digit of calendar year) Year code (last 2 digits of calendar year) Week code (week of January 1 is week ‘01’) Alphanumeric traceability code Pb-free JEDEC designator for Matte Tin (Sn) This package is Pb-free. The Pb-free JEDEC® designator e( 3 ) can be found on the outer packaging for this package. In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line, thus limiting the number of available characters for customer-specific information. Standard PICmicro® device marking consists of Microchip part number, year code, week code and traceability code. For PICmicro device marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price. 2009-2016 Microchip Technology Inc. DS40001393C-page 47 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 12.2 Package Marking Information (Continued) 20-Lead QFN (4x4x0.9 mm) PIN 1 PIN 1 Legend: XX...X Y YY WW NNN e3 * Note: * Example AR1021 I/ML e3 1042256 Customer-specific information Year code (last digit of calendar year) Year code (last 2 digits of calendar year) Week code (week of January 1 is week ‘01’) Alphanumeric traceability code Pb-free JEDEC designator for Matte Tin (Sn) This package is Pb-free. The Pb-free JEDEC® designator e( 3 ) can be found on the outer packaging for this package. In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line, thus limiting the number of available characters for customer-specific information. Standard PICmicro® device marking consists of Microchip part number, year code, week code and traceability code. For PICmicro device marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price. DS40001393C-page 48 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 12.3 Note: Ordering The AR1011/AR1021 are recommended for new designs. The AR1010/AR1020 are still supported and available, but are not recommended for new designs. TABLE 12-1: ORDERING PART NUMBERS Communication Type Temp. Range AR1011-I/ML UART AR1011-I/SO UART AR1011-I/SS AR1011T-I/ML Part Number Pin Package Packing -40°C to + 85°C QFN, 20 pin Tube -40°C to + 85°C SOIC, 20 pin Tube UART -40°C to + 85°C SSOP, 20 pin Tube UART -40°C to + 85°C QFN, 20 pin T/R AR1011T-I/SO UART -40°C to + 85°C SOIC, 20 pin T/R AR1011T-I/SS UART -40°C to + 85°C SSOP, 20 pin T/R AR1021-I/ML I2C/SPI -40°C to + 85°C QFN, 20 pin Tube AR1021-I/SO I2C/SPI -40°C to + 85°C SOIC, 20 pin Tube AR1021-I/SS I2C/SPI -40°C to + 85°C SSOP, 20 pin Tube AR1021T-I/ML I2C/SPI -40°C to + 85°C QFN, 20 pin T/R AR1021T-I/SO I 2C/SPI -40°C to + 85°C SOIC, 20 pin T/R AR1021T-I/SS I2C/SPI -40°C to + 85°C SSOP, 20 pin T/R AR1010-I/ML UART -40°C to + 85°C QFN, 20 pin Tube AR1010-I/SO UART -40°C to + 85°C SOIC, 20 pin Tube AR1010-I/SS UART -40°C to + 85°C SSOP, 20 pin Tube AR1010T-I/ML UART -40°C to + 85°C QFN, 20 pin T/R AR1010T-I/SO UART -40°C to + 85°C SOIC, 20 pin T/R AR1010T-I/SS UART -40°C to + 85°C SSOP, 20 pin T/R AR1020-I/ML I2C/SPI -40°C to + 85°C QFN, 20 pin Tube AR1020-I/SO I2C/SPI -40°C to + 85°C SOIC, 20 pin Tube AR1020-I/SS I2C/SPI -40°C to + 85°C SSOP, 20 pin Tube AR1020T-I/ML I2C/SPI -40°C to + 85°C QFN, 20 pin T/R AR1020T-I/SO 2 I C/SPI -40°C to + 85°C SOIC, 20 pin T/R AR1020T-I/SS I2 -40°C to + 85°C SSOP, 20 pin T/R C/SPI 2009-2016 Microchip Technology Inc. DS40001393C-page 49 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 12.4 Package Details The following sections give the technical details of the packages. /HDG3ODVWLF6KULQN6PDOO2XWOLQH 66 ±PP%RG\>6623@ 1RWH )RUWKHPRVWFXUUHQWSDFNDJHGUDZLQJVSOHDVHVHHWKH0LFURFKLS3DFNDJLQJ6SHFLILFDWLRQORFDWHGDW KWWSZZZPLFURFKLSFRPSDFNDJLQJ D N E E1 NOTE 1 1 2 e b c A2 A φ A1 L1 8QLWV 'LPHQVLRQ/LPLWV 1XPEHURI3LQV L 0,//,0(7(56 0,1 1 120 0$; 3LWFK H 2YHUDOO+HLJKW $ ± %6& ± 0ROGHG3DFNDJH7KLFNQHVV $ 6WDQGRII $ ± ± 2YHUDOO:LGWK ( 0ROGHG3DFNDJH:LGWK ( 2YHUDOO/HQJWK ' )RRW/HQJWK / )RRWSULQW / 5() /HDG7KLFNQHVV F ± )RRW$QJOH /HDG:LGWK E ± 1RWHV 3LQYLVXDOLQGH[IHDWXUHPD\YDU\EXWPXVWEHORFDWHGZLWKLQWKHKDWFKHGDUHD 'LPHQVLRQV'DQG(GRQRWLQFOXGHPROGIODVKRUSURWUXVLRQV0ROGIODVKRUSURWUXVLRQVVKDOOQRWH[FHHGPPSHUVLGH 'LPHQVLRQLQJDQGWROHUDQFLQJSHU$60(<0 %6& %DVLF'LPHQVLRQ7KHRUHWLFDOO\H[DFWYDOXHVKRZQZLWKRXWWROHUDQFHV 5() 5HIHUHQFH'LPHQVLRQXVXDOO\ZLWKRXWWROHUDQFHIRULQIRUPDWLRQSXUSRVHVRQO\ 0LFURFKLS 7HFKQRORJ\ 'UDZLQJ &% DS40001393C-page 50 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 20-Lead Plastic Shrink Small Outline (SS) - 5.30 mm Body [SSOP] Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging 0.65 0.45 SILK SCREEN c Y1 G X1 E RECOMMENDED LAND PATTERN Units Dimension Limits E Contact Pitch Contact Pad Spacing C Contact Pad Width (X20) X1 Contact Pad Length (X20) Y1 Distance Between Pads G MIN MILLIMETERS NOM 0.65 BSC 7.20 MAX 0.45 1.75 0.20 Notes: 1. Dimensioning and tolerancing per ASME Y14.5M BSC: Basic Dimension. Theoretically exact value shown without tolerances. Microchip Technology Drawing No. C04-2072B 2009-2016 Microchip Technology Inc. DS40001393C-page 51 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging DS40001393C-page 52 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging 2009-2016 Microchip Technology Inc. DS40001393C-page 53 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging DS40001393C-page 54 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER /HDG3ODVWLF4XDG)ODW1R/HDG3DFNDJH 0/ ±[[PP%RG\>4)1@ 1RWH )RUWKHPRVWFXUUHQWSDFNDJHGUDZLQJVSOHDVHVHHWKH0LFURFKLS3DFNDJLQJ6SHFLILFDWLRQORFDWHGDW KWWSZZZPLFURFKLSFRPSDFNDJLQJ D D2 EXPOSED PAD e E2 2 E b 2 1 1 K N N NOTE 1 TOP VIEW L BOTTOM VIEW A A1 A3 8QLWV 'LPHQVLRQ/LPLWV 1XPEHURI3LQV 0,//,0(7(56 0,1 1 120 0$; 3LWFK H 2YHUDOO+HLJKW $ 6WDQGRII $ &RQWDFW7KLFNQHVV $ 2YHUDOO:LGWK ( ([SRVHG3DG:LGWK ( 2YHUDOO/HQJWK ' ([SRVHG3DG/HQJWK %6& 5() %6& %6& ' &RQWDFW:LGWK E &RQWDFW/HQJWK / &RQWDFWWR([SRVHG3DG . ± ± 1RWHV 3LQYLVXDOLQGH[IHDWXUHPD\YDU\EXWPXVWEHORFDWHGZLWKLQWKHKDWFKHGDUHD 3DFNDJHLVVDZVLQJXODWHG 'LPHQVLRQLQJDQGWROHUDQFLQJSHU$60(<0 %6& %DVLF'LPHQVLRQ7KHRUHWLFDOO\H[DFWYDOXHVKRZQZLWKRXWWROHUDQFHV 5() 5HIHUHQFH'LPHQVLRQXVXDOO\ZLWKRXWWROHUDQFHIRULQIRUPDWLRQSXUSRVHVRQO\ 0LFURFKLS 7HFKQRORJ\ 'UDZLQJ &% 2009-2016 Microchip Technology Inc. DS40001393C-page 55 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER 1RWH )RUWKHPRVWFXUUHQWSDFNDJHGUDZLQJVSOHDVHVHHWKH0LFURFKLS3DFNDJLQJ6SHFLILFDWLRQORFDWHGDW KWWSZZZPLFURFKLSFRPSDFNDJLQJ DS40001393C-page 56 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER APPENDIX A: DATA SHEET REVISION HISTORY Revision A (07/2009) Original release of this data sheet. Revision B (03/2012) Updated data sheet. Revision C (07/2016) Updated Table 4-1 corrections. and Table 5-1. 2009-2016 Microchip Technology Inc. Other minor DS40001393C-page 57 AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER APPENDIX B: DEVICE DIFFERENCES Modifying, removing or adding components may adversely affect touch performance. Specific manufacturers and part numbers are provided only as a guide. Equivalents can be used. TABLE B-1: Label BILL OF MATERIALS Quantity Value Description Manufacturer C1 1 10 uF Capacitor – Ceramic, 10 uF, 20%, 6.3V, X7R, 0603 AVX 06036D106MAT2A C2 1 0.1 uF Capacitor – Ceramic, 0.1 uF, 10%, 16V, X7R, 0603 AVX 0603YC104KAT2A AVX 06035C103KAT2A NXP PESD5V0S1BA C3, C4, C5(1) 2-3 D1-D8(2) 4-8 130W Diode – Bidirectional, 130W, ESD Protection, SOD323 R1 1 20 K Resistor – 20 K, 1/10W, 5%, 0603 U1 1 N/A Note 1: 2: 0.01 uF Capacitor – Ceramic, 0.01 uF, 10%, 50V, X7R, 0603 Touch controller IC Part Number Yageo America RC0603JR-0720KL Microchip AR1011 or AR1021 C5 is only needed for 5-wire applications. D1-D8 are for ESD protection. - 4-wire touch screen, use D1-D4 - 5-wire touch screen, use D1-D5 - 8-wire touch screen, use D1-D8 See Section 3.8 “ESD Considerations” and Section 3.9 “Noise Considerations” for important information regarding the capacitance of the controller schematic hardware. DS40001393C-page 58 2009-2016 Microchip Technology Inc. AR1000 SERIES RESISTIVE TOUCH SCREEN CONTROLLER THE MICROCHIP WEBSITE CUSTOMER SUPPORT Microchip provides online support via our website at www.microchip.com. This website is used as a means to make files and information easily available to customers. Accessible by using your favorite Internet browser, the website contains the following information: Users of Microchip products can receive assistance through several channels: • Product Support – Data sheets and errata, application notes and sample programs, design resources, user’s guides and hardware support documents, latest software releases and archived software • General Technical Support – Frequently Asked Questions (FAQ), technical support requests, online discussion groups, Microchip consultant program member listing • Business of Microchip – Product selector and ordering guides, latest Microchip press releases, listing of seminars and events, listings of Microchip sales offices, distributors and factory representatives • • • • Distributor or Representative Local Sales Office Field Application Engineer (FAE) Technical Support Customers should contact their distributor, representative or Field Application Engineer (FAE) for support. Local sales offices are also available to help customers. A listing of sales offices and locations is included in the back of this document. Technical support is available through the website at: http://microchip.com/support CUSTOMER CHANGE NOTIFICATION SERVICE Microchip’s customer notification service helps keep customers current on Microchip products. Subscribers will receive e-mail notification whenever there are changes, updates, revisions or errata related to a specified product family or development tool of interest. To register, access the Microchip website at www.microchip.com. Under “Support”, click on “Customer Change Notification” and follow the registration instructions. 2009-2016 Microchip Technology Inc. DS40001393C-page 59 Note the following details of the code protection feature on Microchip devices: • Microchip products meet the specification contained in their particular Microchip Data Sheet. • Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions. • There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft of intellectual property. • Microchip is willing to work with the customer who is concerned about the integrity of their code. • Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable.” Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act. Information contained in this publication regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights unless otherwise stated. Trademarks The Microchip name and logo, the Microchip logo, AnyRate, dsPIC, FlashFlex, flexPWR, Heldo, JukeBlox, KeeLoq, KeeLoq logo, Kleer, LANCheck, LINK MD, MediaLB, MOST, MOST logo, MPLAB, OptoLyzer, PIC, PICSTART, PIC32 logo, RightTouch, SpyNIC, SST, SST Logo, SuperFlash and UNI/O are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. ClockWorks, The Embedded Control Solutions Company, ETHERSYNCH, Hyper Speed Control, HyperLight Load, IntelliMOS, mTouch, Precision Edge, and QUIET-WIRE are registered trademarks of Microchip Technology Incorporated in the U.S.A. Analog-for-the-Digital Age, Any Capacitor, AnyIn, AnyOut, BodyCom, chipKIT, chipKIT logo, CodeGuard, dsPICDEM, dsPICDEM.net, Dynamic Average Matching, DAM, ECAN, EtherGREEN, In-Circuit Serial Programming, ICSP, Inter-Chip Connectivity, JitterBlocker, KleerNet, KleerNet logo, MiWi, motorBench, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM, PICDEM.net, PICkit, PICtail, PureSilicon, RightTouch logo, REAL ICE, Ripple Blocker, Serial Quad I/O, SQI, SuperSwitcher, SuperSwitcher II, Total Endurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. Microchip received ISO/TS-16949:2009 certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona; Gresham, Oregon and design centers in California and India. The Company’s quality system processes and procedures are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping devices, Serial EEPROMs, microperipherals, nonvolatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001:2000 certified. QUALITY MANAGEMENT SYSTEM CERTIFIED BY DNV == ISO/TS 16949 == DS40001393C-page 60 Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries. GestIC is a registered trademark of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of Microchip Technology Inc., in other countries. All other trademarks mentioned herein are property of their respective companies. © 2009-2016, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. ISBN: 978-1-5224-0761-4 2009-2016 Microchip Technology Inc. Worldwide Sales and Service AMERICAS ASIA/PACIFIC ASIA/PACIFIC EUROPE Corporate Office 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support: http://www.microchip.com/ support Web Address: www.microchip.com Asia Pacific Office Suites 3707-14, 37th Floor Tower 6, The Gateway Harbour City, Kowloon China - Xiamen Tel: 86-592-2388138 Fax: 86-592-2388130 Austria - Wels Tel: 43-7242-2244-39 Fax: 43-7242-2244-393 China - Zhuhai Tel: 86-756-3210040 Fax: 86-756-3210049 Denmark - Copenhagen Tel: 45-4450-2828 Fax: 45-4485-2829 India - Bangalore Tel: 91-80-3090-4444 Fax: 91-80-3090-4123 France - Paris Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79 India - New Delhi Tel: 91-11-4160-8631 Fax: 91-11-4160-8632 Germany - Dusseldorf Tel: 49-2129-3766400 Atlanta Duluth, GA Tel: 678-957-9614 Fax: 678-957-1455 Hong Kong Tel: 852-2943-5100 Fax: 852-2401-3431 Australia - Sydney Tel: 61-2-9868-6733 Fax: 61-2-9868-6755 China - Beijing Tel: 86-10-8569-7000 Fax: 86-10-8528-2104 Austin, TX Tel: 512-257-3370 China - Chengdu Tel: 86-28-8665-5511 Fax: 86-28-8665-7889 Boston Westborough, MA Tel: 774-760-0087 Fax: 774-760-0088 China - Chongqing Tel: 86-23-8980-9588 Fax: 86-23-8980-9500 Chicago Itasca, IL Tel: 630-285-0071 Fax: 630-285-0075 Cleveland Independence, OH Tel: 216-447-0464 Fax: 216-447-0643 Dallas Addison, TX Tel: 972-818-7423 Fax: 972-818-2924 Detroit Novi, MI Tel: 248-848-4000 Houston, TX Tel: 281-894-5983 Indianapolis Noblesville, IN Tel: 317-773-8323 Fax: 317-773-5453 Los Angeles Mission Viejo, CA Tel: 949-462-9523 Fax: 949-462-9608 New York, NY Tel: 631-435-6000 San Jose, CA Tel: 408-735-9110 Canada - Toronto Tel: 905-695-1980 Fax: 905-695-2078 China - Dongguan Tel: 86-769-8702-9880 China - Guangzhou Tel: 86-20-8755-8029 China - Hangzhou Tel: 86-571-8792-8115 Fax: 86-571-8792-8116 China - Hong Kong SAR Tel: 852-2943-5100 Fax: 852-2401-3431 China - Nanjing Tel: 86-25-8473-2460 Fax: 86-25-8473-2470 China - Qingdao Tel: 86-532-8502-7355 Fax: 86-532-8502-7205 China - Shanghai Tel: 86-21-5407-5533 Fax: 86-21-5407-5066 China - Shenyang Tel: 86-24-2334-2829 Fax: 86-24-2334-2393 China - Shenzhen Tel: 86-755-8864-2200 Fax: 86-755-8203-1760 India - Pune Tel: 91-20-3019-1500 Japan - Osaka Tel: 81-6-6152-7160 Fax: 81-6-6152-9310 Japan - Tokyo Tel: 81-3-6880- 3770 Fax: 81-3-6880-3771 Korea - Daegu Tel: 82-53-744-4301 Fax: 82-53-744-4302 Korea - Seoul Tel: 82-2-554-7200 Fax: 82-2-558-5932 or 82-2-558-5934 Malaysia - Kuala Lumpur Tel: 60-3-6201-9857 Fax: 60-3-6201-9859 Malaysia - Penang Tel: 60-4-227-8870 Fax: 60-4-227-4068 Philippines - Manila Tel: 63-2-634-9065 Fax: 63-2-634-9069 Germany - Karlsruhe Tel: 49-721-625370 Germany - Munich Tel: 49-89-627-144-0 Fax: 49-89-627-144-44 Italy - Milan Tel: 39-0331-742611 Fax: 39-0331-466781 Italy - Venice Tel: 39-049-7625286 Netherlands - Drunen Tel: 31-416-690399 Fax: 31-416-690340 Poland - Warsaw Tel: 48-22-3325737 Spain - Madrid Tel: 34-91-708-08-90 Fax: 34-91-708-08-91 Sweden - Stockholm Tel: 46-8-5090-4654 UK - Wokingham Tel: 44-118-921-5800 Fax: 44-118-921-5820 Singapore Tel: 65-6334-8870 Fax: 65-6334-8850 Taiwan - Hsin Chu Tel: 886-3-5778-366 Fax: 886-3-5770-955 Taiwan - Kaohsiung Tel: 886-7-213-7828 China - Wuhan Tel: 86-27-5980-5300 Fax: 86-27-5980-5118 Taiwan - Taipei Tel: 886-2-2508-8600 Fax: 886-2-2508-0102 China - Xian Tel: 86-29-8833-7252 Fax: 86-29-8833-7256 Thailand - Bangkok Tel: 66-2-694-1351 Fax: 66-2-694-1350 06/23/16 2009-2016 Microchip Technology Inc. DS40001393C-page 61