Keywords: meter; microcontroller; micro printer; IC card?
Changsha 410083, China;
2.Shandong AssociaTIon of Plant Engineering, Jinan 250011, China)
Keywords: taximeter; microprocessor; micro printer; IC card
1.1 The voice module takes into account the miniaturization and intelligentization of the price meter product. The voice chip adopts the ISDl420 chip with higher integration. Its biggest feature is that it uses EEPROM to directly access analog information without going through A / D and D / A conversion . It has a microphone amplifier, automatic gain control clock, speaker drive circuit, etc. It is powered by + 5V power supply.
The interface between the voice module and the main system is shown in Figure 2. The main system is connected to the ISDl420 chip through the PA port of the 8155 expansion chip. In the design process, the fixed voice part (boarding, getting off the vehicle) information is stored in different starting addresses in ISDl420. During the operation process, different voice functions can be played according to the different operating states of getting on and off the bus. When the voice chip is working, the system first transfers the main program pointer to the playback processing program, finds the pronunciation unit in ISDl420 according to the pronunciation address, and then sends the signal to the speaker to emit sound. After the main CPU completes the sound sending program, it immediately transfers to other subroutines. ?
After power-on, use software to initialize DSl2887, that is, write initial values â€‹â€‹to each register.
This system has designed an intelligent micro-printing circuit separately: It is connected to the host by means of an interface board. This feature allows the bill printing of the meter to be functionally integrated with the main system, but can be performed separately during inspection and maintenance. The micro-printing head used in this system is the Model â€”â€” 15 0â…¡ type printing head produced by EPSON. It is a mechanical dot matrix 4-pin printing mechanism with four horizontally mounted electromagnets on the same carriage for injection. The micro-printing uses a separate single-chip system, taking into account the performance requirements of micro-printing, using Intel's 8 051 chip. The micro-touch is connected to the main MCU through a parallel interface, and its interface diagram is shown in Figure 5. When the data to be printed appears on the printer I / O0 ~ I / O7, as long as the STB changes from high level to low level, and then from low level to high level, the data can be sent to the printer. At this time, the printer sets the BUSY line to busy (high level) and prohibits the input of new data. After the printer takes the data and processes it, the BUSY line is set to idle (low level) and sends an answer pulse ACK to notify the system. You can enter the data again. ?
In this system, the IC card is connected to the PC port of 8155. The specific connection is: the PCI port is connected to the reset terminal RST of the card socket, the PC0 port is connected to the clock terminal CLK of the card socket, the PC2 port is connected to the data input and output terminal I / O of the card socket, and the PC3 port is connected to the VDD terminal of the card socket.
The power supply of the IC card adopts the independent power supply and is controlled by 8052. When a card is inserted, it begins to provide the required power to the IC card. If you insert a bad card or metal piece that is broken by the power supply and the ground, it will cause a short circuit in the power supply circuit and interfere with the operation of the entire device. Using IC card independent power supply mode, when the IC card power supply short circuit occurs, the power regulator forms a short circuit protection due to output overload, and the output is low. When the CPU detects a low level, the power supply to the IC card is interrupted. ?
This is a dual-plug master control American WIFI socket. The main function is to use the mobile phone software to control the switch and timing of the socket through WIFI connection. Before using the device function, you need to configure the network first, that is, let the product connect to the Internet through WIFI. This WIFI can be a router or a mobile phone hotspot.
Outdoor Multi Outlet,Outdoor Socket Outlet,Remote Control Wall Plugs,Remote Control Electrical Outlet
Changxing Potek Electronics & Technology Co,. Ltd , https://www.cn-envirotech.com