HT1635A/B Wearable Sports Bracelet LED Display Application

Transcription

1 HT6A/B Wearable Sports Bracelet LED Display Application HT6A/B Wearable Sports Bracelet LED Display Application D/: A09E Introduction The HT6A and HT6B are Holtek display data memory mapping LED driver devices, whose driving capacity is up to patterns composed of rows and 8 commons. The HT6A provides a -wire serial interface and the HT6B provides an I C interface. Both interfaces are used for MCU data communication. Using the HT66F0 as the host MCU, a demo with two HT6A devices or two HTB devices is taken as an example in this application note to introduce how to use the HT6A and HT6B. Each HT6A or HT6B device on the demo drives 8 commons and rows of RGB LEDs (8 RGB LEDs), showing the wearable sports bracelet LED panel display functions. Operating Principles HT6A and HT6B Main Features Operating voltage:.v ~.V Integrated 6kHz RC oscillator Frame Rate: 00Hz Maximum display capacity: patterns ( rows and 8 commons) Up to 88 RAM display data storage Supports up to 6-level PWM brightness control Four blinking modes: Off, 0.Hz, Hz and Hz COM driving method selectable: MOS open-drain or PMOS open-drain HT6A provides a -wire serial interface, HT6B provides an I C serial interface Cascade function for extending applications Package: 6-pin LQFP / 9 A09E

2 HT6A/B Wearable Sports Bracelet LED Display Application HT6A/HT6B Features Description Communication Interface Based on their interface difference, the HT6 series falls into two versions, the HT6A and the HT6B. The HT6A includes a -wire serial communication interface which has four pins, WRB (Write Serial Clock), DATA (Serial Data), RDB (Read Serial Clock) and CSB (Chip Select). The HT6B is supplied in the same package type as the HT6A and is basically pin compatible with the HT6A, with the exception that the HT6B includes an I C communication interface which has four different pin names corresponding to the HT6A serial interface pins, SCL (Serial Clock), SDA (Serial Data), A (Device Address Data Input Pin) and A0 (Device Address Data Input Pin), as shown in the table below. Interface Pin Part umber Interface Type HT6A -wire DATA WRB RDB CSB HT6B I C SDA SCL A A0 COM and ROW I/O Driving Capacity The HT6A/HT6B devices have a strong current driving capacity for COM and ROW I/Os, more associated parameters are described below. V DD=.V~.V, Ta= C. Symbol Parameter V DD Test Conditions Conditions Min. Typ. Max. Unit V DD Operating Voltage..0. V I OL ROW Sink Current V V OL=0.V 0 ma I OH ROW Source Current V V OH=.V ma I OL COM Sink Current V V OL=0.V 0 00 ma I OH COM Source Current V V OH=.V ma As shown in the above table, the HT6A/HT6B devices support a large COM I/O sink current with a typical value of 00mA, which coupled with the typical -70mA of ROW I/O source current makes the devices more suitable for driving common cathode LED matrixes. The current flowing through the LED is associated with the operating voltage and the LED forward voltage, V F. In some applications, users can use a direct drive method, which means LED anodes are connected to ROW I/Os and LED cathodes are connected to COM I/Os without requiring any current limiting resistor. It should be noted that the HT6A/HT6B pins LEDVDD and VDD, LEDVSS and VSS are internally bonded together respectively, which means that driver power pins, LEDVDD and LEDVSS, and logic power pins, VDD and VSS, are not separated. / 9 A09E

3 HT6A/B Wearable Sports Bracelet LED Display Application COM Driving Methods Each HT6A/HT6B COM pin has two driving types, MOS open-drain and PMOS open-drain. o matter what driving type is selected for the COM pins, the ROW pins only output the data in the corresponding RAM Display Memory. If the RAM is written with a, its corresponding ROW pin will output a high level, similarly, a 0 value corresponds to a low level output. The COM driving setup for the two communication interfaces are shown below. Communication Interface COM Driving Method ID Command Code Default Setup -wire MOS driving PMOS driving XXX-X 000-XXX-X 000-0XXX-X (MOS driving) I C MOS driving PMOS driving XXXXXXX0 XXXXXXX 00H (MOS driving) ote: X : 0 or Operating Modes The HT6A/HT6B devices support three operating modes, Master Mode0, Master Mode and Slave Mode. With regard to Master Mode0 and Master Mode, the system clock can be sourced from the integrated 6 khz RC oscillator or from the external clock on the OSC pin, as shown in the following table. ame Master/Slave Select Input Clock Source OSC Pin Status S Pin Status ote RC Master Mode0 RC Master Mode Master Mode On Chip RC Oscillator Output Hi-Z Always Output High Only Single Chip Application Output Output EXT CLK Master Mode0 EXT CLK Master Mode Master Mode External OSC Input Always Output High Only Single Chip Application Input Output Slave Mode Slave Mode External OSC Input Input The HT6A/HT6B S pin is used for LED driving waveform synchronisation allowing the cascading of more HT6 devices to drive a larger screen. Regarding the HT6A, which has a -wire interface, users can make one device operate in the Master Mode and the remaining devices operate in the Slave Mode. Connect the OSC and S pins of the Master Mode device to the corresponding pins on the Slave Mode devices. Use the host MCU to control the CSB pin on each HT6A device to achieve cascade driving. With respect to the HT6B, which has an I C interface, the A0 and A pins can be configured as pull-high or pull-low to setup the I C slave device address. A four devices cascade function is available. / 9 A09E

4 HT6A/B Wearable Sports Bracelet LED Display Application After system power is applied, the HT6A/HT6B devices will be initialised by an internal power-on reset circuit. The status of the internal circuits after initialisation is as follows. System oscillator will be off COM0~COM7 outputs are high impedance ROW outputs will all be low The LED display will be in an off state ROW outputs are set to 6/6 PWM duty The blinking function will be in an off state It should be noted that data transfers on the -wire/i C bus should be avoided for more than ms following a power-on reset to the devices to allow the reset initialisation operation to complete. Dimming Circuit The HT6A/HT6B devices have an integrated 6-level PWM dimming circuit. The dimming circuit uses the command received by the interface to set up the related dimming register. In this way, all of the ROW outputs duty can be adjusted to implement the brightness control of the entire display screen. The ROW dimming timing is shown in the following figure. / 9 A09E

5 Demo H/W Block Diagram HT6A/B Wearable Sports Bracelet LED Display Application System Block Diagram COM/ROW RGB LED Matrix (8COM x ROW x ) HT6A/B x (6LQFP) -wire/i C Key x Top Board AC00V~0V DC V AC-DC Converter (FAS0--W) Micro USB HT66F0 (8SOP) 860 Li+ Battery Power Supply Circuit DC-DC Boost Circuit (S7066) Li+ Battery Charger (APL0) Bottom Board Figure System Block Diagram The demo PCB is composed of two boards, a top board and a bottom board. The top board is an RGB LED Matrix board and the bottom board is a power control board. These two boards are connected using a pin header. RGB LED Matrix Two HT6A devices or two HT6B devices jointly drive an RGB LED Matrix composed of 8 commons and 8 rows. Power Supply Circuit The power supply circuit provides three power supply methods, AC power (00~0V AC), power adapter (DCV, Micro USB interface) and a Li-battery (one 860). DC-DC Boost Circuit When only using the Li-battery to supply power, enable the DC-DC boost IC (S7066) which will increase the battery voltage to V to supply power for the host MCU and the HT6A/HT6B. Li-Battery Charging Circuit When using the AC power or the external power adapter to supply power, enable the Li-battery charging management IC (APL0) to charge the battery. Key Section A touch key is used for switching the display screens. Host MCU Section This demo uses the HT66F0 as the master control MCU to implement data communication with the HT6A/HT6B and achieve various display functions. / 9 A09E

6 HT6A/B Wearable Sports Bracelet LED Display Application Application Circuits Figure RGB LED Matrix Circuit The RGB LED Matrix PCB is available for the HT6A and HT6B. Switching between these two devices can be achieved by using several 0Ω resistors, therefore a general device name HT6 is used in the schematic diagram. 6 / 9 A09E

7 HT6A/B Wearable Sports Bracelet LED Display Application F A fuse J AC DIP SOCKET U FG Z C ZR 0.uF/7VAC L VCC V+ C C D 000uF/V 0.uF V- TVS/SMAJ6.0CA R K R 0K D SS IO_ACI C 0nF D SS IO_USBI C 0nF R K R 0K D9 TVS/MSMP6.0A R7' R7 R6 R C6 uf/0v/06 MICRO USB 0R/080 0R/080 VDD 0R VDD 0R FAS0--W C0 VOUT uf/0v/06 C C7 C8 C9 R 70K 0uF/6V/7 U C0 0 R PVOUT FB uf/0v/06 9 LX LBO 8 LBI VBAT PGD LBI 7 uf/0v/06 L SGD E 6 VOUT RS608TRMGJ I SVOUT C9 uf/0v/06 R8 00K LBI S7066_DF0 R9 uf IO_BOOSTE R0 Q R 0K 0K R 00K R 00K VBAT VOUT C.7uF D VDD D SS SS VBAT R 0R R7 D7 LED U IO_CHG_DET STAT ISET VBAT GD S BATT VI R APL0-SOT- J 00K AD_BATV R6 C Li+ BAT/.7V Battery Box R8 K VDD C.7uF Q R0 R9 0K IO_BAT_CHGE U VI VOUT C 0.uF GD HT7-SOT89 ADC_VREF C 0uF nf 00K GD VDD VDD J J RST ICPCK ICPDA KE RDB CSB CSB WRB DATA C6 C 0.uF D8 8 ICPDA R 6 00K 7 R 00R RST 8 IO_CHG_DETR 0R 9 R 0 C7 0.uF RESET_KE PA0/C0X/TP0_0/A0 VSS/AVSS PB/XT PB/XT PB/OSC PB/OSC VDD PB0/RES PC/TPB_/SCOM PC0/TPB_0/SCOM0 PC7/[TPA]/SCOM PC6/[TP0_0]/SCOM PD/[TCK]/TP_0/[SDO] PD/[TCK0]/[SDI/SDA] U PA/TPA/A PA/TCK0/C0+/A PA/IT0/C0-/A PA/IT/TCK/A PA/CX/SDO/A PA6/SDI/SDA/A6 PA7/SCK/SCL/A7 PB/SCS/VREF PC/TCK/PCK/C+ PC/PIT/TP_0/C- PC/[IT0]/[PIT]/TCK/TP_ PC/[IT]/TP0_/TPB_/[PCK] PD0/[TCK]/TP_/[SCS] PD/[TP_0]/[SDO]/[SCK/SCL] HT66F0-8SOP-A IO_BAT_CHGE ICPCK AD_BATV IO_ACI IO_USBI IO_BOOSTE ADC_VREF R 0R DATA C8 R6 FB/7 WRB R7 0R CSB 0.uF R8 0R CSB R9 0R RDB R0 0R KE R R DATA WRB Figure Power Control Board Circuits Power Supply Circuits VDD J F A fuse AC DIP SOCKET Z C ZR 0.uF/7VAC U FG L VCC V+ C C D 000uF/V 0.uF V- TVS/SMAJ6.0CA R K R 0K D SS IO_ACI C 0nF D SS IO_USBI C 0nF R K R 0K D9 TVS/MSMP6.0A R7' R7 R6 R C6 MICRO USB uf/0v/06 0R/080 0R/080 VDD 0R VDD 0R FAS0--W Figure AC Power and Power Adapter (Micro USB) Power Supply Circuit VBAT S R 00K AD_BATV C R6 00K nf J Li+ BAT/.7V Battery Box Figure 860 Li-battery Power Supply Circuit 7 / 9 A09E

8 HT6A/B Wearable Sports Bracelet LED Display Application The demo supports the following three power supply methods: AC Power The AC power (00~0VAC) flows through a 0V/A fuse, then a D7 varistor and a 0.μF X safety capacitor and finally will be converted to a V/A DC power by an AC-DC module. Power Adapter Use an external DCV/A power adapter to supply power via a Micro USB interface. Li-battery This demo provides an 860 Li-battery holder. When the battery power key S is switched on, use a 860 Li-battery to supply power. Since the operating voltages for the host MCU and the HT6A/HT6B are set to V, when using the Li-battery to supply power, the DC-DC boost circuit must be used to increase the battery voltage to V. Each power type is connected with a Schottky diode SS to be isolated from the other two power sources. The IO_ACI port is used to detect whether an AC power is connected and the IO_USBI port is used to detect whether an external power adapter is connected. When the MCU detects an AC power or an external power adapter, the DC-DC boost circuit will be turned off. DC-DC Boost Circuit C7 C8 C0 VOUT uf/0v/06 C C9 R 70K 0uF/6V/7 U C0 PVOUT FB uf/0v/06 LX LBO VBAT PGD LBI uf/0v/06 L SGD E RS608TRMGJ I SVOUT C9 uf/0v/06 R8 00K LBI S7066_DF0 R9 uf IO_BOOSTE R LBI VOUT Q R 0K R 0K R 00K R 00K VBAT VOUT C.7uF D SS VDD D SS VBAT Figure 6 DC-DC Boost Circuit When there is no AC power or external power adapter connected, the demo will use a Li-battery to supply power. When the battery voltage is higher than.v, the MCU IO_BOOSTE port will output a low level to enable the DC-DC boost IC S7066, which will increase the battery voltage to V and provide a A output current. This demo uses SILERG s S7066 for the boost IC. It has a supplied package type of QF -0, an input voltage as low as.8v, an output voltage of.v~.v which is adjustable by changing the resistance value of R and R, as well as a 6A peak current. 8 / 9 A09E

9 HT6A/B Wearable Sports Bracelet LED Display Application Li-battery Charging Circuit IO_CHG_DET J Li+ BAT/.7V Battery Box R7 U STAT ISET GD BATT VI APL0-SOT- D7 LED C.7uF R8 VDD K Q R0 R9 0K IO_BAT_CHGE Figure 7 Li-battery Charging Circuit When the MCU detects that an AC power or an external power adapter is connected, its IO_BAT_CHGE port will output a high level to enable the Li-battery power management IC, APL0, which will charge one 860 Li-battery. The APL0 used in this demo is APEC s product that has a supplied package type of SOT-, an input voltage of.v~6.v and a charging current of 0.A~0.A which is adjustable by changing the R8 resistance value. When the battery voltage is increased to.v, charging operation stops, when the battery voltage falls to.0v, charging operation restarts. The R8 resistance value is K and the charging current is about 00mA. When the LED D7 is on, it indicates that the Li-battery is charging, when it is off, it indicates that the battery power is full. RGB LED Matrix Driving Circuit R R R6 R7 R8 R9 R0 R R R R R R6 R7 R8 R9 G R B6 G6 R6 B7 G7 R7 B8 G8 R8 B9 G9 R9 B0 G0 U HT6-6LQPF VDD B R R R G R B R0 R R9 G R8 C B R7 R R6 0.uF G R B R R R G R B R VDD OSC ROW ROW ROW ROW6 ROW7 ROW8 ROW9 ROW0 ROW ROW ROW ROW ROW ROW6 ROW7 ROW8 ROW ROW9 ROW ROW0 ROW0 ROW ROW9 ROW ROW8 ROW LED_VDD ROW ROW7 ROW ROW6 LED_VDD ROW ROW6 ROW ROW7 ROW ROW8 ROW ROW9 ROW ROW0 ROW0 ROW VSS ROW OSC ROW DATA WRB RDB CSB S VDD COM0 LED_VSS COM COM COM COM COM COM6 COM7 LED_VSS R0 R R R R R R6 R7 R8 R9 R0 R R R0 B G R B G R B G R B G R C 0.uF VDD C uF DATA R FB/7 WRB R 00R C C 0pF 00R R0 R8 RDB COM VDD COM COM COM COM COM6 COM7 COM8 R9 00R S C CSB C C6 RDB VDD R6 R7 R8 CSB R9 nf 9 / 9 A09E

10 HT6A/B Wearable Sports Bracelet LED Display Application 0 / 9 A09E Figure 8 RGB LED Display Circuit (HT6A/B Section) Figure 9 RGB LED Display Circuit (COM Driving Section) ROW ROW ROW0 ROW9 ROW8 LED_VDD 6 ROW7 7 ROW6 8 ROW 9 ROW 0 ROW ROW ROW ROW0 VSS OSC 6 DATA 7 WRB 8 RDB 9 CSB 0 S VDD COM0 LED_VSS COM COM 6 COM 7 COM 8 COM 9 COM6 0 COM7 LED_VSS ROW ROW ROW ROW0 6 ROW9 7 ROW8 8 ROW7 9 ROW6 0 LED_VDD ROW ROW ROW ROW ROW 6 ROW0 7 ROW9 8 ROW8 9 ROW7 0 ROW6 ROW ROW ROW ROW ROW 6 ROW0 7 ROW9 8 ROW8 9 ROW7 60 ROW6 6 ROW 6 ROW 6 ROW 6 U HT6-6LQPF COM0 COM9 COM COM COM COM COM COM6 R6 R7 R8 R9 R R R R R6 R7 R8 G6 G7 G8 G0 G G G G G6 G7 G8 B6 B7 B8 B0 B B B B6 B7 B8 B VDD 0.uF C6 VDD OSC S CSB R R6 R7 R8 R9 R0 R R R R R R6 R7 R8 R9 R60 R6 R6 R6 R6 R6 R66 R67 R68 R69 R70 R7 R7 R7 R7 R7 R76 R77 R78 R79 R80 R8 R8 R8 R8 R R VDD 0.uF C7 VDD 0.uF C8 RDB R R R R VDD CSB R B G R0 G9 B9 R G B 00R R K R R nf C7 RDB WRB DATA FB/7 R0 0R R C8 R8 R86 R87 COM- R88 R89 R90 COM- R9 R9 R9 COM- R9 R9 R96 COM- R97 R98 R99 COM- R00 R0 R0 COM-6 R0 R0 R0 COM-7 R06 R07 R08 COM-8 R09 R0 R COM9 R R R COM0 R R6 R7 COM R8 R9 R0 COM R R R COM- R R R6 COM-6 R7 R8 R9 COM-7 R0 R R COM-8 COM COM COM COM COM COM6 COM7 COM8 COM- COM- COM- COM- COM COM COM COM6 Q Q Q Q Q Q6 Q7 Q8 Q9 Q0 Q Q Q Q Q Q6

11 HT6A/B Wearable Sports Bracelet LED Display Application R87 COM- COM R8 R86 Q LED-R LED-G LED-B R R R R G B Figure 0 Single RGB LED Driving Method Each HT6A or HT6B device on the LED display board drives a 8 pattern RGB LEDs (8 commons and rows). Two devices combine to drive a 8 8 pattern RGB LED matrix. This demo uses Everlight s 9-7B RGB SMD LED, which has four pins and is a common cathode type. A single LED size is.6mm.6mm, which is the equal to two 060 SMD resistors. The LED-R s V F is about.7v~.v, the LED-G s and LED-B s V F is about.6~.v and the maximum I F is ma. In order to obtain a higher LED brightness level, the HT6A/HT6B operating voltage is set to V, a 0Ω resistor is connected between the ROW I/O and the LED-R anode, a 00Ω resistor is connected between the ROW I/O and the LED-G/LED-B anode. For those LEDs that are controlled by the same COM, their cathodes are connected together to a MOS () drain terminal. The HT6A/HT6B COM pins are set as PMOS open-drain outputs to control the external MOS on/off switching to provide a stronger COM driving capacity. When all LEDs are on, the operating current will exceed A. If the COM pins are set as MOS open-drain outputs, a high current will directly flow into the HT6A/HT6B, which will generate a device over temperature condition, which could cause damaged. To avoid unexpected damage, this driving method is not suggested. This demo uses a COM PMOS open-drain driving method together with an external MOS to drive the common cathode LED matrix. Since the COM pins are set as PMOS open-drain outputs, when writing a logic to these pins, their integrated PMOS will be on and they will output a high level (LEDVDD). When writing logic 0 to them, their integrated PMOS will be off and they will be in the high impedance state. Usually, connecting a pull-low resistor in parallel between the external MOS Gate and Source terminals can provide a dissipation path for the MOS source charge stored during the COM pin high level output, by which the MOS can be turned off. The part number for all MOS components on the demo is. Connecting a resistor in parallel between the gate and source terminals can achieve normal MOS on/off control. Touch Key Detection Circuit D C 0 TVS/SMAJ6.0CA KE KE Figure Touch Key Circuit As shown in the above figure, if the host MCU key detection I/O s internal pull-high resistor is enabled, when the key is pressed, the detection I/O will be pulled-low. D is an ESD protection component. This key is used to switch the RGB LED Matrix display functions. / 9 A09E

12 HT6A/B Wearable Sports Bracelet LED Display Application MCU Control Circuit C6 C 0.uF ICPDA D8 R K 7 R 00R RST 8 IO_CHG_DETR 0R 9 R 0 C7 0.uF RESET_KE PA0/C0X/TP0_0/A0 VSS/AVSS PB/XT PB/XT PB/OSC PB/OSC VDD PB0/RES PC/TPB_/SCOM PC0/TPB_0/SCOM0 PC7/[TPA]/SCOM PC6/[TP0_0]/SCOM PD/[TCK]/TP_0/[SDO] PD/[TCK0]/[SDI/SDA] U PA/TPA/A PA/TCK0/C0+/A PA/IT0/C0-/A PA/IT/TCK/A PA/CX/SDO/A PA6/SDI/SDA/A6 PA7/SCK/SCL/A7 PB/SCS/VREF PC/TCK/PCK/C+ PC/PIT/TP_0/C- PC/[IT0]/[PIT]/TCK/TP_ PC/[IT]/TP0_/TPB_/[PCK] PD0/[TCK]/TP_/[SCS] PD/[TP_0]/[SDO]/[SCK/SCL] HT66F0-8SOP-A IO_BAT_CHGE ICPCK AD_BATV IO_ACI IO_USBI IO_BOOSTE ADC_VREF R 0R DATA R6 FB/7 WRB R7 0R CSB R8 0R CSB C8 0.uF R9 0R RDB R0 0R KE DATA R WRB R GD VDD VDD J KE RDB CSB CSB WRB DATA J RST ICPCK ICPDA U VI VOUT C 0.uF GD HT7-SOT89 ADC_VREF C 0uF Figure MCU Control Circuit As the host MCU, the HT66F0 is mainly used to transfer data with the HT6A/B via a -wire interface or an I C interface and control the driver device to drive the RGB LED Matrix for various display functions. In addition, the HT66F0 detects whether AC power or an external power adapter is connected. It uses its A/D converter to sample the battery voltage, controls the APL0 to charge the battery or not and determines whether the S7066 is turned on for a battery voltage boost function. The HT66F0 has an integrated -bit SAR A/D converter, whose reference voltage is provided by the MCU operating voltage being regulated to.v using the HT7. In the figure above, the pin header J is used for the HT6A/HT6B power and interface pins connection. J is used for the HT66F0 In-Circuit programming pin connection. HT66F0 I/O Control Functions: MCU Pin Circuit Label Control Function 9 IO_CHG_DET APL0 charging status detection KE Detects the key used for switching display functions 6 RDB -wire interface read serial clock 7 CSB -wire interface HT6A chip selection 8 CSB -wire interface HT6A chip selection 9 WRB I C/-wire interface serial clock 0 DATA I C/-wire interface serial data IO_BOOSTE DC-DC boost enable control IO_USBI External power adapter detection IO_ACI AC power detection 6 AD_BATV Li-battery voltage detection 8 IO_BAT_CHGE Li-battery charging enable control / 9 A09E

13 HT6A/B Wearable Sports Bracelet LED Display Application S/W Flowchart The HT6A/HT6B demo board programs, written using assembly language, include the main program, display subroutine, key scanning subroutine, power supply detection subroutine, Li-battery power detection subroutine and timer interrupt subroutine, etc. Owing to the different communication interfaces, there are two versions of programs that have different data transfer methods but share the remaining subroutines. The main program and several major subroutines will be described in the following section. Main Program Flowchart Start Power On Delay 00ms MCU RAM and registers and HT6A/B initialisation CLR WDT TB0F =? TB0F = 0 Power supply detection Li-battery? Li-battery power detection Key scanning s finished? Update system clock 0ms finished? Battery Power <.V? Update display Figure Main Program Flowchart / 9 A09E

14 HT6A/B Wearable Sports Bracelet LED Display Application When the demo board is powered-on, the HT66F0 will implement a system initialisation, provide a 00ms delay to ensure that the HT6A/HT6B internal power-on reset circuit has enough time to complete the reset operation and then communicate with the HT6A/HT6B for initial setup. In the main program loop, the host MCU firstly detects the power supply method and then executes a key scanning, system clock update and display update. HT6A/HT6B Initialisation Flowchart Start COM Driving Type Setup: PMOS Blinking Frequency Setup: Blinking Off PWM Duty Setup: 6/6 PWM Duty Operating Mode Setup: RC Master Mode0 SS Setup: SS E LED Setup: LED O Return Figure HT6A Initialisation Flowchart (-wire Interface) / 9 A09E

15 HT6A/B Wearable Sports Bracelet LED Display Application Start HT6B Addresses: IC AA0=b, IC AA0=0b COM Driving Type Setup: PMOS Blinking Frequency Setup: Blinking Off PWM Duty Setup: 6/6 PWM Duty Operating Mode Setup: RC Master Mode0 SS & LED Setup: SS E & LED O Return Figure HT6B Initialisation Flowchart (I C Interface) Before the HT6A/HT6B can drive the LED Matrix, some initialisation setup should first be executed, such as address setup (only for the HT6B), COM driving type setup, blinking frequency setup, PWM duty setup, operating mode setup, system setup and LED setup, etc. After all these initialisation setups are completed, the HT6A/HT6B data RAM can be written with values for the LED display. / 9 A09E

16 HT6A/B Wearable Sports Bracelet LED Display Application Display Subroutine Flowchart Start System On Mode? Full screen white light on and blinks three times at a frequency of 0.Hz Welcome Mode? After once scroll of HOLTEK logo and welcome characters, enter the automatic demonstration screen. If the key is long-pressed, enter the normal display mode. ormal Display Mode?. Time Display Mode: display the setup time.. Heart Beat Mode: display the heart rate.. Meter Step Mode: increase one step each 0.s and clear to zero when reaching ten thousand steps.. Connection Mode: enter the bluetooth connection screen automatically.. Charging Mode: enter the battery charging screen, after a full charge enter the time display mode. 6. Gaming Mode: enter Tetris game screen automatically. Short-press the key to switch between sub-modes. If the previous mode is welcome mode, long-press the key to enter fuel consumption display mode. If the previous mode is time adjustment mode, long-press the key to enter welcome mode. Fuel Consumption Display Mode?. Fuel Consumption: switch between "FUEL" character and value screens every s.. Time: switch between "HOURS" character and time screens every s.. Calories Consumption: switch between "CALS" character and value screens every s.. Steps: switch between "STEPS" character and value screens every s.. Goal Completion Rate: switch between "GOAL" character and rate screens every s. Short-press the key to switch between sub-modes. Long-press the key to enter time adjustment mode. Time Adjustment Mode?. Adjust hour high digit, this digit blinks at a frequency of Hz.. Adjust hour low digit, this digit blinks at a frequency of Hz.. Adjust minute high digit, this digit blinks at a frequency of Hz.. Adjust minute low digit, this digit blinks at a frequency of Hz. Short-press the key to adjust each digit value. Long-press the key to switch between digits. After all digits have been adjusted, long-press the key to enter normal display mode's sub-mode, time display mode. Return Figure 6 Display Subroutine Flowchart The display subroutine is used to update the RGB LED Matrix display contents. There are five major modes, system on mode, welcome mode, normal display mode, fuel consumption display mode and time adjustment mode. Each of the last three modes has several sub-modes. Switching between these five major modes is achieved by a key long press. Switching between sub-modes under a major mode or adjusting a time digit value is achieved by a key short press. 6 / 9 A09E

17 HT6A/B Wearable Sports Bracelet LED Display Application Touch Key Processing Subroutine Flowchart Start First long-press? Second long-press? Third long-press? Fourth long-press? Fifth long-press? Sixth long-press? Seventh long-press? Eighth long-press? Return Switch to normal display mode. Under this mode, short-press key to switch between sub-modes. Switch to fuel consumption display mode. Under this mode, short-press key to switch between sub-modes. Switch to hour high digit adjustment mode, short-press key to adjust this digit value. Switch to hour low digit adjustment mode, short-press key to adjust this digit value. Switch to minute high digit adjustment mode, short-press key to adjust this digit value. Switch to minute low digit adjustment mode, short-press key to adjust this digit value. Switch to normal display mode. Under this mode, short-press key to switch between sub-modes. Switch to welcome mode. Short-pressing key is not valid. Long-press key to clear the counter to zero. Figure 7 Touch Key Processing Subroutine Flowchart The touch key processing subroutine is used for RGB LED Matrix display mode screen switching operations. In the time adjustment mode, a short key press is used to adjust the digit value. A long key press is used to confirm the current digit value. In the other major modes, a long key press is used to switch to other major modes and a short key press is used to switch to other sub-modes of the current major mode. 7 / 9 A09E

18 HT6A/B Wearable Sports Bracelet LED Display Application Power Supply Detection Subroutine Flowchart Start AC power connected? Turn off DC-DC Boost function First power-on? Power adapter connected? Enable Li-battery charging Li-battery power supply, Set the related flag high Return Figure 8 Power Supply Detection Subroutine Flowchart The MCU uses the IO_ACI and IO_USBI ports to detect an AC power connection or an external V DC power adapter connection respectively. If there is no AC power or power adapter detected, it indicates that the demo is using the Li-battery as its power supply. If an AC power or an external power adapter is connected, the Li-battery boost circuit will be turned off. Then, when a 860 Li-battery is placed in the battery holder, the battery charging function will be turned on. Li-battery Power Detection Subroutine Flowchart Start Li-battery power supply? System On Mode? Turn off Li-battery charging Li-battery power<.v? Battery placed? Turn off DC-DC boost circuit, Turn off Li-battery charging, Clear HT6A/B RAM data Turn on DC-DC boost circuit, Turn off Li-battery charging Turn on Li-battery charging Return Figure 9 Li-battery Power Detection Subroutine Flowchart When the demo uses a Li-battery as its power supply, the Li-battery power detection subroutine is used to detect the current battery voltage. If the battery voltage is higher than.v, the DC-DC boost circuit will be turned on. If the battery voltage is lower than.v, this indicates a low battery power, in which case the DC-DC boost circuit and the LED Matrix display function will be turned off. 8 / 9 A09E

19 HT6A/B Wearable Sports Bracelet LED Display Application Example Code The demo example codes configuration options are shown below. Refer to the attachment section for the detailed code. ;=============================================================; ;SysVolt:.0V ;SysFreq: HIRC MHz ;WDT: By S/W Control ;WDT clock source fs: f SS/ ;I/O or Reset function: RESB ;SIM Function: Disable ;LVR Function: Enable ;LVR Voltage Selection:.0V ;=============================================================; Conclusions This application note has introduced the HT6A/HT6B main features and used some example code and application circuits to show how to use the HT6A/HT6B LED driving functions. Attachments Source Code Files -wire Interface Communication CODE I C Interface Communication CODE Schematic Files Operating Description Files 9 / 9 A09E