【導(dǎo)讀】圖U21A、U21B、U21C、U21D表示的是同一塊芯片EP1C6Q240C8，有240個(gè)引腳，邊上的引腳與主板焊接起來(lái)。片，比如說(shuō)BGA，PGA一般都采用這種技術(shù)；萬(wàn)用表或者示波器來(lái)測(cè)試各個(gè)通路便于修理。機(jī)來(lái)進(jìn)行專門(mén)的焊接工作。SMD表面安裝技術(shù)在PCB電路板上安裝布線。CPU中80286、80386和某些486主板采用這種封裝形式。這里的SMD表示的是貼片組裝器件；隨著集成電路技術(shù)的發(fā)展，對(duì)集成電路的封裝要求更加嚴(yán)格。這是因?yàn)榉庋b技術(shù)關(guān)系。BGA一出現(xiàn)便成為CPU、主板上南/北橋芯片等高。密度、高性能、多引腳封裝的最佳選擇。類型的芯片封裝來(lái)對(duì)該器件進(jìn)行封裝操作；封裝完成之后進(jìn)行DRC檢測(cè)，然后更新到PCB，即EP1C6Q240C8主體部分，該部分引腳有點(diǎn)多；期間處于從屬地位。配置數(shù)據(jù)通過(guò)DATA0引腳送入FPGA。由JTAG標(biāo)準(zhǔn)決定，通過(guò)JTAG. 時(shí)鐘信號(hào)是時(shí)序邏輯的基礎(chǔ)，它用于決定邏輯單元中的狀態(tài)何時(shí)更新。時(shí)鐘邊沿觸發(fā)信號(hào)意味著所有的狀態(tài)變化都發(fā)生在時(shí)鐘邊沿到來(lái)時(shí)刻。在FPGA中還有電平觸發(fā)方式，這里就不作介紹，僅做了解。

　　

【正文】 nal production process on the first chip after a preprogrammed reloading to board change accordingly, simplified process for the first fixation device to the circuit board, then the JTAG programming, so as to greatly accelerate the progress of the project. JTAG interface for PSD chip inside all parts of programming. The embedded system design, some highend microprocessor with JTAG interface, convenient and multi objective system for testing, but also can achieve flash programming. (norflash smaller capacity, equivalent to the memory, nandflash is equivalent to the puter39。s hard drive, large capacity ) The U21C module represents the chip power supply and grounding If I remember correctly, the general chip is used in TTL level, the level can provide different voltage to meet different needs. The number of electricity which is widely used in. It has14 pins are connected to + , another 12pin connection is + , we can put the power supply part with a capacitor to ground, the benefits of this is to filter out the power of internally generated some highfrequency crosstalk signal, ground part are simulated, some digital ground, so alone up the advantage of preventing signal interference, intermediate with a single inductor to connect, so can hinder the high frequency signal is directly coupled。 U21D represents a clock signal input Map we found, for the four clock input pin we only CLK2a pin, such benefits are later we can also extend the welding some signals of different frequencies reserved for standby。 The clock signal is temporal logic based, it is used for decision logic unit in the state when the update. The clock signal is a fixed cycle and running the semaphore, the clock frequency ( clock frequency, CF ) is the countdown clock cycle. Clock edge trigger signal means that all state changes have occurred in the edge of the clock arrival time. At the edge of the trigger mechanism, only the rising or falling edge is the effective signal to the control logic unit, a state quantity change. As in the end is a rising edge or the trailing edge as effective trigger signal, depending on the logic design technology. In FPGA and level trigger manner, here is not described, only know. In three, EP1C6Q240C8 on the internal functional ponents: The second part I from schematic perspective to the analysis of this chip, we have the following overall observation of the whole chip A core board based on Altera, EP1C6, Cyclone device embedded system development provides a A very good hardware platform, it provides developers with the following resources: The 1 main chip using Altera Cyclone device EP1C6Q240C8 2EPCS1I8 configuration chip 34 user defined buttons 44 userdefined LED 51seven segment LED code 6 standard AS interface and JTAG debugging interface 7 50MHz high accuracy clock source 8three high density interface 9 system power on reset circuit 10support +5V direct input, board power management module System main chip with240pins, SMD package E1C6FPGA, it has 6030LE, 26M4K RAM (total239616bits ),2 high performance PLL and up to 185 users Custom IO. At the same time, the system can also be based on user demand for the design to replace the other different series Core board, such as: EP1C12, EP2C20, EP3C25 etc.. Therefore, no matter from the performance, Or from the system flexibility, whether you are a beginner, or senior hardware engineer, it will Be your good helper. EP1C6 core board system function frame diagram: FPGA platform provides a wealth of resources for students or developers to learn to use, resource pack The interface munication, control, storage, data conversion and interactive display of several major modules, interface. Communication module includes the SPI interface, IIC interface, VGA interface, RS232 interface, USB interface, PS2 key Disk / mouse interface,1Wire interface。 storage module includes a EEPROM memory module。 data The conversion module includes a serial ADC, DAC and audio CODE。 interactive display module includes 8 Keys,16 LED light emitting diode display,1602 character dotmatrix LCD,8 bit dynamic7 segment code tube, Real time clock, SD card, etc.. These resource module can meet the beginners entry requirements, Can also meet the developer carried out two times the development requirements. EDA / SOPC experiment development platform to provide resources: In 1, the standard configuration for EP1C6core board core board ( core chip for the EP1C6Q240C8). Can be Replacement of the EP2C20F484C8and other core plate. 2,1602 character dotmatrix lcd. In 3, RTC, to provide realtime clock. 4,1and 256color VGA interface. 5,1 standard serial interface. In 6, the 1USB device interface, using PDIUSBD12chip to realize USB protocol conversion. 7, based on the SPI or IIC interface audio CODEC module. 8,1buzzer output module. In 9, the 2 PS2keyboard / mouse interface. 10, serial ADC and serial DAC module. In 11, IIC interface EEPROM memory module. In 12,1Wire interface based on digital temperature sensor. 13,8 bit dynamic seven segment code tube LED display. 14,16user LED display, a 8user defined key output. In 15, an SD card interface module. Extended interface for users, high speed stable free expansion. 16X16 lattice and a key circuit analysis SN74HC154DW, ., the lower left corner of the chip,16 line decoder. SN74HC154DW is a8 bit shift register and a memory, three state output function. Shift registers and memory are separate clock. Data on the rising edge of SHcp input, at the rising edge of STcp into a storage register. If the two clock together, then the shift register is always smaller than the storage registers as a pulse. The shift register has a serial shift input, and a serial output, and an asynchronous low level reset, storage register has a parallel in 8, with three state output of the bus,