1. Introduction to PIC Easy R2
PIC Easy R2 is a product which was designed and manufactured by AT-COM giving users the convenience combine ATCBus with PIC18FJ Microchip microcontrollers series. The board supports to connect the computer via USB Full Speed V2.0, with a USB HID Bootloader that allows users to load firmware directly into the PIC microcontroller without any other programming kit. In addition, the PIC18F87J50 microcontroller with 48MHz processor speed combined with the Dual ATCBus Host Socket design maximizes the microcontroller's resources to meet the needs of programmers developing applications. Especially with convenient data output, PIC Easy R2 will bring you the most modern and sophisticated design inspiration.
2. Design Diagram of PIC Easy R2
3. Features of PIC Easy R2
- Power supplies for PIC Easy R2 are available through the following connectors:
- 5VDC via USB mini connector (6).
- 5VDC via Terminal Connector (8).
- 3.7V Li-Po battery through Connector (11).
- The outstanding feature of the PIC Easy R2 is its built-in backup online, which can switch between the 5VDC power source and the battery for mobility and stable operation in the event of a power failure.
- This feature is based on the TPS61092 IC Boost Converter with the input voltage of 1.8 - 5.5V and the output current that meets the application need current up to 2A.
- Battery for the board is Lithium - Polymer 3.7V rechargeable battery and recharged from 5VDC power via MCP73832T charging IC with 4.2V charging voltage and 100mA charging current, fully automatic charging mode to maximize the longevity of Battery.
- The charger also has a function is charging battery status indicator through Charging LED Indicator(10), while charging the Led light is red when the battery is fully charged, Led off.
- Low battery indicator function is also integrated is displayed through Low Battery LED Indicator (12). When the voltage of the battery drops below 3.3V, the Led light is red.
- The board is integrated ON / OFF switch, the user can set the switch to ON or OFF to open or shut down the power for the circuit. In addition, users can connect to the external switch via External ON / OFF Switch (4).
- PIC Easy R2 is equipped with powerful PIC18F87J50 microcontroller with USB V2.0 Full Speed 12 Mb/s, clock frequency up to 48 MHz, 128KB Flash memory, 3,904 bytes RAM combined with Dual ATCBus Host Socket optimized peripheral of microcontroller allows PIC Easy R2 to easily combine multiple ATCBus boards to perform applications such as GSM, GPRS, GPS, etc.
- The board is equipped with a reset button, two blue LEDs, two push buttons, all located at the bottom of the board:
- The reset button is used to reset the PIC18F87J50 microcontroller, when the reset button is pressed, the voltage at the MCLR pin of PIC18F87J50 changes from logic 1 to logic 0.
- 2 blue Led visual indicators or in case users need to debug code when programming. 2 Led connected to PIC18F4550 via RE0 and RE1 pins, positive when the output of RE0, RE1 at logic level 1.
- When the push button action changes the pins RB4, RB5 of the PIC from logic 1 to logic 0.
- The board is designed with 2 headers with the I/O of PIC18F87J50 placed along the 2 sides of PIC Easy R2.
- Dual ATCBus Host Socket with pins Analog, SPI, I2C, Timer, PWM, UART, ... according to ATCBus standard helps users connect to the Easy Board to experience the "Plug and Play" feature of PIC Easy R2.
4. USB HID Bootloader of PIC Easy R2
The board supports the USB HID Bootloader feature which allows direct programming of the PIC18F87J50 without programming kit. In addition, users can load programs for PIC18F87J50 using ICSP Header.
The Hid Bootloader is loaded into the Program Memory of the PIC18F87J50 in each PIC Easy R2 product. The Hid Bootloader uses the memory area of Program Memory from address 0x000 to 0x0FFF. This memory area is used for storage for the Hid Bootloader. So when a user writes an application running on PIC Easy R2, they need to declare the address for the Map Reset vector and the Map interrupts vector so that there is no memory overlap when the PIC18F87J50 starts. The user should change as follows:
//reserve boot block area (0x000-0x0FFF)
//map reset vector at 0x1000
//map interrupt vector from 0x01008 to 0x1018
This is done depending on the compiler that you use to compile into File.hex for your application such as MPLAB C18 Compiler, CCS Compiler, HI- TECH C Compiler ...
To enter the USB HID Bootloader mode of PIC Easy R2 we do the following:
- Connect PIC Easy R2 to PC via USB mini on board. Then press holds the SW1/RB4 button and presses the RESET button. The PIC Easy R2 will enter the HID Bootloader mode. When entering the HID Bootloader mode, the LD1/RE1 Led and the LD2/RE0 Led will flashes continuously, waiting for the user to update the Firmware for the PIC18F87J50.
- When connected to a computer, the PIC Easy R2 will automatically install drivers for the user's computer without having to install any drivers for PIC Easy R2.
- To load firmware for user application running on PIC Easy R2, users can use USB Bootloader V2.9j program of Microchip to flash Firmware to Program Memory of PIC18F87J50.
- After downloading USD Bootloader V2.9j to your computer, extract the WinRAR file and click the HIDBootloader.exe file to run the USB Bootloader program on your computer.
- After running USB Bootloader V2.9j, select Import Firmware Image and select the path to the .hex file store.
- After successfully importing file.hex, select Erase/Program/Verify Device to load the file.hex to Program Memory of PIC18F87J50.
- After successfully loading the file.hex you can choose Reset Device to enable the PIC18F87J50 to run the program you have programmed.
5. Dimension of PIC Easy R2
6. Demo application
Locate coordinates and display them on Google Map