8051 Basic Development Board. Product Manual. Contents. 1) Overview 2) Features 3) Using the board 4) Troubleshooting and getting help

Transcription

1 8051 Basic Development Board Product Manual Contents 1) Overview 2) Features 3) Using the board 4) Troubleshooting and getting help

2 1. Overview 2. Features The board is built on a high quality FR-4(1.6 mm) board with a green solder mask and a clear and legible white legend Onboard Serial and USB(optional) interface options for easy connection to external devices and computers Onboard rectifier enables the board to be used with AC and DC input powers and provides reverse polarity protection Onboard 5V regulator with heatsink for best performance Power Status LED(Green) along with a general purpose LED connected to P1.0 General purpose switch connected to Onboard quartz crystal Mhz oscillator circuit Port extensions for all ports Onboard power bus for Vin, Gnd and 5V lines External pull-up resistors for Port 0 Comes with a detailed product manual and an excellent after sales support Compatible with Atmel s AT89S51 and AT89S52, Phillips P89V51RD2 and other 40 pin 8051 devices Note: The P89V51RD2 is highly suggested for use with this board as it can be directly programmed through the serial and the USB port without the need for an external hardware programmer. All programs for AT89S51 and AT89S52 are compatible with the P89V51RD2 and can be used with it without any changes.

3 3. Using the board The 8051 Basic Development Board consists of everything needed to get started with 8051 programming easily. It sports an onboard power regulator, crystal ossilator, reset circuit, Serial RS232 and USB connections for easy connections to external devices and computers, port extentions for all ports, etc. Power Supply The board consists of a DC Jack to which the input power has to be applied. The board can work on voltages withing the range of 7-15V. The board can accept both DC and AC voltages and provides reverse polarity protection. This power input is first rectified and then regulated to output a constant 5V. The input voltage, Gnd(-ve), and 5V are provided at the Power Bus and can be used to power external circuits. The onboard 5V regulator can provide a maximum of 1A of current. An onboard power switch controls the power to the board. Alternativly, the board can also be powered of the 5V supply from the USB port when connected to a computer through the USB port on the board. The USB port can provide a maximum current of 100 ma. The boards onboard pheripherals consume a little of this current and leave the rest unused. Hence, only a part of this current is left for the user. Please make sure you do not draw more than 50 ma of current when powered of the USB port, else you may damage your USB port. An onboard power selector(labelled Power Input Selector in the Overview section) can be used to select the power supply to the board between the USB port and the External Power Supply. Putting the jumper between one side of the outer pins selects External Power Input and putting it on the other selects USB power. Once you have the board powered on you should see the green power status LED light up. Serial and USB Connections The board provides an industry standard RS232 interface circuit which can be used to connect the board to an external device with serial interface or to a computer through a serial cable. The board also sports a USB to Serial Converter which can be used to do serial interfacing between the microcontroller and a computer. The board uses the CP2102 IC from Silicon Laboratories for handling the USB to Serial Conversion. The first time you connect the board to a computer, you will be required to install drivers for the board. Please follow our CP2102 Driver Installation Tutorial to install the drivers. A copy of the installation guide is provided on the product CD.

4 Once the drivers are installed you will have to find out the COM port to which board is connected to. To do this right click on the My Computer icon, click on Properties and select the Hardware tab in the dialog box that appears. Under the Hardware tab, click on Device Manager. In the Device Manager Dialog box, open the list Ports (COM & LPT). Note down the COM port number which appears beside the device name Silicon Labs CP210x USB to UART Bridge. You will need the COM port number to tell the computer to which port the board is connected during serial programming and communication. Crystal Oscillator The board by default comes with an onboard crystal oscillator circuit consisting of a MHz quartz crystal and the required capacitors. If you would like to use the microcontroller on a different speed, you may replace this crystal with the crystal of the required frequency. Make sure you replace the capacitors also to match the crystal you use. Please refer the datasheet of the microcontroller for more information. General Purpose LED The board has an onboard general purpose LED which can be switched on and off by the microcontroller. The onboard Red LED is connected to P1.0 on the microcontroller. It is connected to Vcc through a suitable resistor as shown in the circuit. To control the status of the LED, you will first have to set P1.0 as output. To switch on the LED you will have to set P1.0 as low and to switch it off set P1.0 as high. General Purpose Switch The onboard switch can be used to get input signals to the microcontroller. The switch is connected to the pin P0.7 Every time the switch is pressed a low signal appears at P0.7 which is at other times has a high signal. Reset Button The board provides a reset switch which is connected such that it resets the microcontroller every time it is pressed. Upon reset, all registers are set to their default value and the program is executed from the beginning. External Pull-up Resistors for PORT0 All eight pins of PORT0 are by default connected to Vcc through a resistor of 10K Ohms. Port Extentions

5 All IO pins are brought out to male header pins for easy connections with external circuits. Two parallel empty holes are also provided to each IO pin, which can be used to solder in wires directly and provide easy expansion. The pin name and any dual functions of each pin are also printed on the board next to each pin for easy prototyping. Programming the P89V51RD2 with the board If you are using a P89V51RD2, you can program the microcontroller without any external hardware programmer directly from Flash Magic programming software. To program thep89v51rd2, the following steps should be followed a) Once the required program to be uploaded is compiled and the hex file is generated, run Flash Magic and set the parameters on Flash Magic as follows Set COM port to the serial port to which the development board is connected (usually COM1) Set Baud Rate to 9600 bps Set Device to 89V51RD2 Set Interface as None(ISP) Check Erase Blocks used by Hex File Check Verify after programming b) Connect the board to the computer using a serial cable c) Apply power to the board. You should see the Green Power LED light up d) Select the Hex File to be uploaded on Flash Magic and click on Start e) When you get a message indicating you to Reset Device into ISP Mode, reset the microcontroller by pressing the Reset button on the development board f) The Hex file will get uploaded to the microcontroller in a few seconds, after which you may execute the program by Resetting the device again 4. Troubleshooting and Getting Help We are committed to ensure that our customers' projects, designs and research go as efficiently and as smoothly as possible. And for this we promise and provide an excellent after-sales support service. When you contact us for support, please keep the following things in mind - you will have to provide us with the invoice information(order no., date of purchase, etc.) provide us with all the required details(operating system being used, compiler being used, etc) do not ask us questions or doubts about products we do not sell do not contact us 2 days before a project deadline for any sort of immediate or urgent support do not mail us a rephrased version of your project contact us only if you know what you are doing, do not expect any sort of help from our side otherwise