2011 International Coriference on Electronics and Optoelectronics (ICEOE 2011)
Design of Automatic Washing Machine Based on Verilog HDL Language
Chen Xizhenl, Chen Guangjian2, Jia Jinling2,yu han\ Zhou Tianpeng1 Faculty of Automation and Information, Sichuan University of Science and Engineering, Zigong , China; 2. Faculty of Computer Science, Sichuan University of Science and Engineering, Zigong , China; c_xizhen
[email protected],
[email protected],
[email protected],
[email protected]@yeah.net I.
Abstract-As described by digital system the language Verilog HDL is widely used in the circuit design, its own advantages to
be able to use software language describe hardware features that makes it has good readability, portability, etc. Its advantages not only reduce the hardware development cycle but also greatly reduce development costs. This article describes the characteristics and application of Verilog HDL and take the automatic washing machine as examples to illustrate the practicality of HDL. The result of simulation shows this method is feasibility and effectiveness.
Keywords-Verilog; Hardware Automatic washing machine
description
languages;
In recent years, with the development of science and technology, the design of electronic systems also produce a revolutionary change, a new class of development tools relate to electronic systems are spreading quickly. Hardware Description language ( HDL) is a method to Description of digital circuit. HDL describes a certain function of digital circuit usually has one or more files composition. According to certain rules (or grammar) HDL describes documents after the compilation, and uses the electronic system design automation (EDA) tools to comprehensive, just can be transformed into practical circuit. In recent years, with the rapid development of EDA and large scale programmable of logic device, HDL can hierarchical description and simulation of any electronic components characteristics, so that the circuit designers and developers could describe the feature of the circuit freely, which can build the bridge of communication and exchange data between chip designers and producers. 1.
THE INTRODUCE OF
VERILOG HDL
Verilog language is a kind of abstract level of hardware description language. This language supports the early abstract design concept, and could realize the later abstract design. It includes the hierarchical structure, which allows designers to describe the complexity of the control. Verilog HDL is a powerful tool, not only its easy to use but also the strong function, especially the Verilog HDL industrial standardization, conform with the trend of microelectronics technology development. Verilog HDL is used in digital design modeling from the switch level to abstract algorithm design level. This language provides abundant structural. These constructions can not only be used to design pattern on hardware inter current behavior, but also on hardware design of scheduling pattern.
978-1-61284-276-9/11/$26.00 ©2011 IEEE
II.
THE DESIGN OF AUTOMATIC WASHING MACHINE
Because the VerilogHDL has the advantage of powerful language structure and concise code for complex control logic. So, this article based on VerilogHDL to design the control system of the washing machine. A.
The principle of automatic washing machine
The inside bucket of fully-automatic washing machine has many small holes, through them the bucket of water between the inside and outside is interlinked, electromagnetic valve execute the water in and out. When the water in the control system will fill the electromagnetic valve opens, so feed the water into outer barrel. When drainage, the control system will let the drain electromagnetic valve opens, so the water by outer barrel row to drain. When dehydration, the control system will close clutch and by turning on washing motor driving internal vats to dry. High, middle and low water level control switch is used to detect the high, middle and low water level. Start button is used to activate washing machine to work, stop button is used to achieve manually stop water, drainage, dehydration and alarm. Drainage button is to achieve manually drainage. B.
Working function and operational states process of the washing machine
This paper introduces the extensive use of automatic washing machine without any button in each big campus (mainly university), the entire laundry process control all by coin to complete, if need continuous coin, this action and the next action should be in 15 seconds, if exceed 15 seconds, the mashing will carry out the corresponding operation and default last coin to end the action. The machines have four functions: there are dehydrate, express laundry, criterion laundry and delicate whites. For the sake of simplicity, we will do some simplifY, its principle is as follows: 1) This machine adopts toss a coin manner, and should be the one coin. The action should be interval in 15 seconds and only one by one. 2) The machine start executes the operation process in 15 seconds, and the washing machine screen will show the process in digital tube state and program state. Process condition as follows: there are bb for washing process, cc for rinsing process; dd for dehydration process. Program states as follows: 01 for standard procedures, 02 for big things program, 03 for quick procedure, 04 for single off
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2011 International Coriference on Electronics and Optoelectronics (ICEOE 2011)
program. 3) There are four working ways of automatic washing machine. If you pay one yuan, the mashing will execute dehydration operation after 15 seconds, if you continue to pay one yuan in 15 seconds the machine will recognize and it is executed express laundry operation. If you pay another one yuan in 15 seconds but in 15 seconds later without the forth coin it is executed the third operating :standards laundry, if have four coins then execute the fourth operation: big things laundry. figure 1 shows the states of the automatic washing machine .
motor. The full laundry process is completed and the speaker sends out the continuous 15 seconds of hasty "di, di" sound, which tells user laundry end and controller returns to the initial state again. Designing and realizing washing machine
C.
the programs of automatic
Verilog HDL language designs and realizes the input or output programm of automatic washing machine. The flowchart of design the program is shown in figure 3:
Figure I. The state of automatic washing machine
When the washing machine executes express laundry operation it has six working status. There are: free, adding water, washing, draining, drying, and beeping. The figure of state transition is shown in figure2: rst
idle m 0
start
f------t
� =0 cl=0
Water
7s
I-----
W�l m�O
Wash
;k: L�d�r�Y� ---.J---I.- < det ect> r--------� -� yes ...
9s
t--
=0 cl=0
beep
Figure3. The flowchart of design the program drain � m�O d�l w=0
6s
f----.
5s
dry
I-----
m=1
d�l w=0
beep
/
15s r--
m�O, d�O
Figure2.the work chafe of automatic washing machine
Laundry process: A) Open power then start program, the circuit is reset to initial condition, the control signal is m = 0, w = 0, d = 0. When press start button the program wiIJ enter the state of water!, w = 1, then open water valve continuing 7s to adding water. According the rotation current of motor estimates the weight of clothing to decide water level and washing time. (That based on cleaning index of manufacturing standards). B) Start fill solenoid valves when the water reached requirement shutdown water pushing solenoid valves. C) Start motor to catharsis and this moment is w = 0, m = 1, which makes motor start operation, the process last for 9s, and close motor when washing finish. D) Start drainage electromagnetic valves, the water-level sensor controls the drainage electromagnetic to be closed, and check whether the switch is closed after drainage electromagnetic valve close E) Start clutch and drying motor, when drying close jilt dry ,
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*
signal definition: clk: Clock input; reset The reset signal of the system; oneyuan: Representative into one yuan coin; execute_d: Representative start washing machine and execute single dehydration operation; execute f: Representative start washing machine execute express laundry operation; execute s: Representative start washing machine execute standard laundry operation; execute b: Representative start washing machine laundry objects larger execute operationo * / Main design program is as follows: input oneyuan,reset,clk; output execute_d,e_f, e_s, e_b reg execute_d,e_f, e_s, e_b reg[2:0] state; parameter idle=O,one=1,two=2,three=3,four=4; always @ (posedge clk) begin itrreset) else begin
2011 International Conference on Electronics and Optoelectronics (ICEOE 2011)
method which can adapt to the social development needs. We use hardware description language form digital system design is not only flexible and convenient but also reduce the cost of development and the development cycle. This design method will plays an increasingly important role in the future digital system design.
case(nextstate) state=idle water: wash: drain: dry: beep: endcase end
ACKNOWLEDGMENT
This work was supported in part by The project of Artificial Intelligence of the Key Laboratory of Sichuan Province(2009RZ003) ;
end assign speaker=clk_1Hz&clk_1 KHz&alarm; D.
The working process of simulation of the automatic washing machine
REFERENCES
When rest signal comes, all of the signals set zeros; then if you put on start button the machine will enter water state. As long as you no longer press start button, washing machine will automatically execute the process according to the predetermined. The simulation results as shown in figure 4. III.
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Wangguan etc. Verilog HDL and digital circuit design [M].beijing mechanical industry press, 2005.9
[2]
XiaYu wen. Verilog digital system design guide [M].beijing: aerospace university press, 2003. 2-10
[3]
Thomas & Moorby, The Hardware Verilog DescriptionLanguage [M]. Beijing tsinghua university press, 2001. 23-36.
[4]
WangJiGang, GuGuoChang. Structures and patterns in communication system software application research (J].journal of computer application pract, ( I I) : 43-45.
[5]
YangJimin YangJiBing, digital system design and VerilogHDL [M].beijing: electronic industry press, 2003,23(11 ):43-45.
[6]
YuanJunQuan, SunMinQi, CaoRui. VerilogHDL digital system design and its application [M].concrete: xian university of electronic science and technology press, 2002.
CONCLUSION
In this paper we adopt Verilog HDL language to design automatic washing machine control system. We use its powerful language structure and concise code to describe the complex control logic. Through comprehend the corresponding hardware circuit and tools of Verilog HDL language to generate more than traditional logical design
Name
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times
W M D
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nextstate
Figure 4. The simulation process of automatic washing machine
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