1, DS1302 used the programmable clock chip , very inaccurate programmable clock chip , depending on the external capacitor programmable clock chip , it is not good to tune, sometimes a few minutes a day can be different, It can only be corrected by software, which is very troublesome. DS3231 is good, only one or two minutes a year, the circuit connection is very simple, very easy to use.
2, timing accuracy is the most key to the crystal oscillator, the crystal oscillator with the single chip microcomputer is very rough work, used to complete simple timing tasks with low precision. To implement the clock must be very wrong. DS1302 is a special clock chip produced by the old United States, which is specially used for clock circuits, and the accuracy is definitely not the same. In addition, it is extremely convenient to use, no longer use timers to achieve interrupt timing, only a simple read can programmable clock chip .
3, DS1302 contents 1 Abstract 1 Introduction 2 The structure and work of DS1302Control volume, turn on or off power amplifier, loop play and stop function. And support perpetual calendar function programmable clock chip , external 32768K crystal oscillator can accurately calculate the year, month, day, hour and second, etc., the function is very powerful, cost-effective.
The data of the time chip is read by the single chip microcomputer. If the on-chip memory is small, the E2PROM needs to be extended to store the time speech and read time data. Voice data refers to the binary data frequency of the pronunciation of numbers between the hours, minutes, seconds and 0-60, which can be generated by the timer of the MCUMake a sound. The voice part can be used to programmable clock chip is relatively simple.
There are two ways to do this, using a chip with a clock function and a voice output function, such as WTV020. The MCU voice chip is used, and the mcu controls the voice chip according to external requirements to combine the built-in voice playback time information. The second way voice chip can choose a wide range, most OTP voice chips can do.
This is based on ds1302 with 1602 display can realize the time (year, month, day, hour, minute, second) display, adjustment, setting and other functions too much may not be complete, you have to carefully change yourself.
Voice chip sta013 can support mp3 playback. You will then cut the voice to be reported, put it into flash, as for how to allocate the flash address this is all in your own. Get a 51 MCU, get a flash, if you want to get a clock chip (not necessarily necessary) programmable clock chip ! Add sta013. Power amplifier circuit, sta013 will not do power amplifier circuit, to find a picture on the Internet can also ring.
can be completely solved by WAV microcontroller with lower sound quality. DAC can not be used, you can refer to the idea of Du Yang SPEAKER32 [open source on his website], you can also directly take R-2R ladder dac on the IO port - if there is too much voice information, add a piece of SPI FLASH such as 25Q16 to save it, and read it when you use it. The power amplifier does need one, and the lm386 should be enough if the requirements are not large.
Cost is different, precision is different. The DS3231M is low cost and high precision. The DS1337 has low power consumption. The DS3231M is a low-cost, high-precision I2C real-time clock (RTC). The device includes a battery input that maintains accurate timing when the main power supply is disconnected. Integrated microelectromechanical systems (MEMS) improve the long-term accuracy of devices and reduce the number of components in the production line. The DS3231M uses the popular DS3231RTC The same device package.
3, this chip parameter is BS27 package, operating voltage from 6V to 18V, 4x25W output power (14V, 10%THD, 4Ω).
4, the dc power supply in ad18 is located in the voltage source library above the drawing symbol. ad, the full name of AltiumDesigner, is an integrated electronic product development system launched by Altium. Double-click the Simulation option under the Type bar to bring up SimModel-VoltageSource/DCSource (Excitation Model - AC /DC Power) dialog box. altium is a software for designing circuit diagrams.
1, digital tube drive circuit design. It is generally driven by a triode such as 9013 or a latch such as 74HC573 to enable it to turn on and off normally. Use dynamic scanning mode to let the niticle display programmable clock chip the number you wantWord, this can be scanned with or without an interrupt. Use a real-time clock chip such as DS1302 to get the time data you want. There are many source programs on the Internet that you can search for.
2, it is estimated that the interrupt in the program is not handled well. I guess it is caused by the direct operation of the programmable clock chip on the port when you use the interrupt. Suggestion: Put the display buffer in RAM, and display the contents of RAM directly called by LED in the main program.
3, with AT89S51 (MCU) design aElectronic clock AT89S51 as the core to form an electronic clock. The circuit is mainly composed of microprocessor (AT89S51), power supply circuit, keyboard circuit and display circuit. When the system is running, 8 LED digital tubes display time, minutes and seconds respectively. It can be adjusted at any time through the keyboard... AT89S51 as the core to form an electronic clock.