DE0_Nano_User_Manual_v1.9 (1162595), страница 3
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This A-to-D provides conversion throughput rates of 50 ksps to 200ksps. It can be configured to accept up to eight input signals at inputs IN0 through IN7. This eightinput signals are connected to the 2x13 header, as shown in Figure 3-10. The remaining I/Os of the2x13 header are a DC +3.3V (VCC33), a GND and 13 pins, which are connect directly to theCyclone IV E device.For more detailed information on the A/D converter chip, please refer to its datasheet which isavailable on manufacturer’s website or under the /datasheet folder of the system CD.20Figure 3-10Pin distribution of the 2x13 HeaderFigure 3-11 shows the connections on the 2x13 header, A/D converter and Cyclone IV device.Figure 3-11Wiring for 2x13 header and A/D converterThe pictures below indicate the pin 1 location of the 2x13 header.21Figure 3-12Pin1 locations of the 2x13 headerTable 3-8 Pin Assignments for 2x13 HeaderSignal NameGPIO_2[0]GPIO_2[1]GPIO_2[2]GPIO_2[3]GPIO_2[4]GPIO_2[5]GPIO_2[6]GPIO_2[7]GPIO_2[8]GPIO_2[9]GPIO_2[10]GPIO_2[11]GPIO_2[12]GPIO_2_IN[0]GPIO_2_IN[1]FPGA Pin No.PIN_A14PIN_B16PIN_C14PIN_C16PIN_C15PIN_D16PIN_D15PIN_D14PIN_F15PIN_F16PIN_F14PIN_G16PIN_G15PIN_E15PIN_E16DescriptionGPIO Connection DATA[0]GPIO Connection DATA[1]GPIO Connection DATA[2]GPIO Connection DATA[3]GPIO Connection DATA[4]GPIO Connection DATA[5]GPIO Connection DATA[6]GPIO Connection DATA[7]GPIO Connection DATA[8]GPIO Connection DATA[9]GPIO Connection DATA[10]GPIO Connection DATA[11]GPIO Connection DATA[12]GPIO InputGPIO InputI/O Standard3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3V3.3VGPIO_2_IN[2]PIN_M16GPIO Input3.3VTable 3-9 Pin Assignments for ADCSignal NameADC_CS_NADC_SADDRADC_SDATADC_SCLKFPGA Pin No.PIN_A10PIN_B10PIN_A9PIN_B14DescriptionChip selectDigital data inputDigital data outputDigital clock input22I/O Standard3.3V3.3V3.3V3.3V3.7 Digital AccelerometerThe ADXL345 is a small, thin, ultralow power, 3-axis accelerometer with high resolutionmeasurement.
This digital accelerometer can be accessed through a SPI 3-wire digital interface orI2C 2-wire digital interface. Main applications include medical instrumentation, industrialinstrumentation, personal electronic aid and hard disk drive protection etc.
Some of the key featuresof this device are listed below. For more detailed information, please refer to its datasheet which isavailable on manufacturer’s website or under the /datasheet folder of the system CD.•••Up to 13-bit resolution at +/- 16gSPI (3- wire) or I2C (2-wire) digital interfaceFlexible interrupts modesFigure 3-13 shows the connections between the ADXL345 and the Cyclone IV E device.Figure 3-13Wiring between the ADXL345 and the Cyclone IV E deviceTable 3-10 Pin Assignments for Digital AccelerometerSignal NameI2C_SCLKI2C_SDATG_SENSOR_INTG_SENSOR_CS_NFPGA Pin No.PIN_F2PIN_F1PIN_M2PIN_G5DescriptionEEPROM clockEEPROM dataG_Sensor InterruptG_Sensor chip selectI/O Standard3.3V3.3V3.3V3.3V3.8 Clock Circuitr yThe DE0-Nano board includes a 50 MHz oscillator.
The oscillator is connected directly to adedicated clock input pin of the Cyclone IV E FPGA. The 50MHz clock input can be used as asource clock to drive the phase lock loops (PLL) circuit. The clock distribution on the DE0-Nanoboard is shown in Figure 3-14.23Figure 3-14Block diagram of the clock distribution3.9 Power SupplyThe DE0-Nano board’s power is provided through the USB 5V power, the 5V VCC pins on the two40-pin headers or the 2-pin power header.
The DC voltage is then stepped down to various requiredvoltages. For portable project applications, connect a battery power supply (3.6~5.7V) to the 2-pinexternal power header shown in Figure 3-15.Figure 3-15Portable Battery Connection24Power Distribution SystemFigure 3-16 shows the power distribution system on the DE0-Nano board.Figure 3-16DE0-Nano Power Distribution System25Chapter 4DE0DE0-Nano Control PanelThe DE0-Nano board comes with a Control Panel facility that allows users to access variouscomponents on the board from a host computer. The host computer communicates with the boardthrough a USB connection. The facility can be used to verify the functionality of components on theboard or be used as a debug tool while developing RTL code.This chapter first presents some basic functions of the Control Panel, then describes its structure inblock diagram form, and finally describes its capabilities.4.1 Control Panel SetupThe Control Panel Software Utility is located in the directory “tools/DE0_NANO_ControlPanel” inthe DE0-Nano System CD.
It's free of installation, just copy the whole folder to your host computerand launch the control panel by executing the “DE0_NANO_ControlPanel.exe”.When Control Panel starts it will attempt to download a configuration file onto the DE0-Nano board.The configuration file contains a design that communicates with the peripheral devices on the boardthat are attached to the FPGA device. Perform the following steps to ensure that the control panelstarts up successfully:1.Make sure Quartus II 10.0 or later version is installed successfully on your PC.2.Connect a USB A to Mini-B cable to a USB (Type A) host port and to the board.3.
Start the executable DE0_NANO_ControlPanel.exe on the host computer. The Control Paneluser interface shown in Figure 4-1 will appear.5. The DE0_NANO_ControlPanel.sof bit stream is loaded automatically as soon as theDE0_NANO_ControlPanel.exe is launched.6. In case the connection is disconnected, click on CONNECT where the .sof will be re-loadedonto the board.Note: the Control Panel will occupy the USB port until you choose to close the program ordisconnect it from the board by clicking the Disconnect button.
While the Control Panel isconnected to the board, you will be unable to use Quartus II to download a configuration file intothe FPGA.268. The Control Panel is now ready for use; experience it by setting the ON/OFF status for someLEDs and observing the result on the DE0-Nano board.Figure 4-1 The DE0-Nano Control PanelThe concept of the DE0-Nano Control Panel is illustrated in Figure 4-2. The “Control Circuit” thatperforms the control functions is implemented in the FPGA board. It communicates with theControl Panel window, which is active on the host computer, via the USB Blaster link.
Thegraphical interface is used to issue commands to the control circuit. It handles all requests andperforms data transfers between the computer and the DE0-Nano board.Figure 4-2 The DE0-Nano Control Panel concept27The DE0-Nano Control Panel can be used to light up LEDs, change the buttons/switches status,read/write to SDRAM Memory, read ADC channels, and display the Accelerometer information.4.2 Controlling the LEDsA simple function of the Control Panel is to allow setting the values displayed on LEDs. Choosingthe LED tab displays the window in Figure 4-3.
Here, you can directly turn the LEDs on or offindividually or by clicking “Light All” or “Unlight All”.Figure 4-3 Controlling LEDs4.3 Switches and PushbuttonsChoosing the Switches tab displays the window in Figure 4-4. The function is designed to monitorthe status of slide switches and pushbuttons in real time and show the status in a graphical userinterface. It can be used to verify the functionality of the slide switches and pushbuttons.28Figure 4-4 Monitoring switches and buttonsThe ability to check the status of pushbutton and slider switches is not needed in typical designactivities.
However, it provides a simple mechanism for verifying if the buttons and switches arefunctioning correctly. Thus, it can be used for troubleshooting purposes.4.4 Memor y ControllerThe Control Panel can be used to write/read data to/from the SDRAM/EEPROM/EPCS on theDE0-Nano board.
As an example, we will describe how the SDRAM may be accessed; the sameapproach is used to access the EEPROM and EPCS. Click on the Memory tab and select “SDRAM”to reach the window in Figure 4-5.29Figure 4-5 Accessing the SDRAMA 16-bit word can be written into the SDRAM by entering the address of the desired location,specifying the data to be written, and pressing the Write button. Contents of the location can be readby pressing the Read button. Figure 4-5 depicts the result of writing the hexadecimal value 06CAinto offset address 200, followed by reading the same location.The Sequential Write function of the Control Panel is used to write the contents of a file into theSDRAM as follows:1.Specify the starting address in the Address box.2.
Specify the number of bytes to be written in the Length box. If the entire file is to be loaded,then a checkmark may be placed in the File Length box instead of giving the number of bytes.3.To initiate the writing process, click on the Write a File to Memory button.4. When the Control Panel responds with the standard Windows dialog box asking for the sourcefile, specify the desired file in the usual manner.The Control Panel also supports loading files with a .hex extension.
Files with a .hex extension areASCII text files that specify memory values using ASCII characters to represent hexadecimalvalues. For example, a file containing the line0123456789ABCDEFdefines eight 8-bit values: 01, 23, 45, 67, 89, AB, CD, EF. These values will be loadedconsecutively into the memory.The Sequential Read function is used to read the contents of the SDRAM and fill them into a file asfollows:301.Specify the starting address in the Address box.2. Specify the number of bytes to be copied into the file in the Length box.
If the entire contentsof the SDRAM are to be copied (which involves all 32 Mbytes), then place a checkmark in theEntire Memory box.3.Press Load Memory Content to a File button.4. When the Control Panel responds with the standard Windows dialog box asking for thedestination file, specify the desired file in the usual manner.Users can use the similar way to access the EEPROM and EPCS. Please note that users need toerase the EPCS before writing data to it.4.5 Digital AccelerometerThe Control Panel can be used to display the status of the Digital Accelerometer where it measuresthe output of its 3-axis (X, Y, Z). The measurement range and resolution is set to default value ±2g(acceleration of gravity) and 10bit twos complement respectively.
Figure 4-6 shows the currentdigital accelerometer status of the DE0-Nano when Accelerometer tab is clicked. The units that aredisplayed are the raw register values converted to decimal. The value in parentheses is thegravitational acceleration values (mg) calculated from the register values according the formula.Table 4-1 shows the rule.Table 4-1 acceleration values convert ruleRegister Value*FormulaResult (mg)00/511*2011/511*23.922/511*26.81717/511*266.4511511/511*2200031Figure 4-6 Digital Accelerometer status4.6 ADCFrom the Control Panel, users are able to view the eight-channel 12-bit analog-to-digital converterreading. The values shown are the ADC register outputs from all of the eight separate channels.
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