51 microcontroller minimum system board is not good after soldering, how to detect the error? What are the common types of errors?
This is very good to check ah, first check the power supply, take the meter to measure the power supply, each point down the measurement, and finally measure the various pins whether there is a soldering, to this are not a problem, then the entire running light program, download into the
, run up to see the I/O are normal, if this is normal, then
Your board success. The board is now ready to go. All that’s left to do is to fulfill your various ideas.
What do I need to solder for the minimum system of 51 microcontroller?
Main chip: AT89S52 (or STC series), one DIP40 socket.
Power supply: 78M05 (voltage regulator), 200uF16V (1), 104 ceramic (1)
(Note: If you use the USB power supply directly, the above can be exempted, directly weld the USB interface a)
Main clock: 11.0592MHz crystal oscillator (or 12MHz) 1, 20 ~ 30p ceramic capacitors two
Reset: one 10k resistor, one 10~100uF capacitor. If manual reset is required, add a welded light touch switch.
Interface: four 8-wire interface, a Respack8 (row resistance, for P0 port pull-up).
How to solder pull-up row resistor in 51 microcontroller minimum system?
First, find the common terminal of the row resistor. The common terminal is on the side of the row resistance labeled with a small white dot. You can also use a multimeter resistance gear measurements, choose any end, measure the resistance of the end and the rest of the pins, if the resistance of the pins are equal, the end of the common terminal, otherwise, the other end of the common terminal.
The common terminal is connected to the microcontroller power supply, and the other pins are connected to the microcontroller IO port.
The specific welding method is the same as welding a normal resistor, but with more pins. You can weld the two ends first, and then weld the center pins after positioning.
How to detect errors when the 51 microcontroller minimum system board doesn’t work well after soldering? What are the common types of errors?
Specifically how not good to use the best to describe. The first is to check whether the power supply is normal, measure the voltage of each chip power supply pins. If the power supply is normal, the minimum system should not be a big problem, and then there is a pin soldering, this can write a routine to run a little. Then analyze which pins have problems.
The minimum system of the 51 microcontroller welding themselves, but to download the program you have to put the microcontroller from the socket key down on the development board, how to do?
Pay attention to the welding of the welding row of pins, respectively, to TXDRXD and then there is the use of the kind of USB to TTL downloader and then use the Dupont cable connection can be a certain treasure have to sell that kind of downloader, the chip is generally used CH340
51 microcontroller minimum system how to realize?
Microcontroller minimum system, or known as the minimum application system, refers to the use of the minimum number of components composed of microcontrollers can work system. For the 51 series of microcontrollers, the minimum system should generally include: microcontroller, power supply, crystal circuit, reset circuit.
89C51 microcontroller a
2, power supply
5V DC power supply 1
3, crystal circuit
including 12MHz crystal 1, 30pF ceramic capacitors 2
4, reset circuit
10uF electrolytic capacitors 1, 4k7 resistor 1. 1 x 4k7 resistor.
The circuit is as follows:
Turn left|Turn right
Note: The /EA (pin 31) in the above figure can also be directly connected to the power supply VCC, 2k resistor can be removed.
51 microcontroller minimum system:
1, clock circuit 51 microcontroller on the clock pins: XTAL1 (19 pins): chip internal oscillator circuit input. XTAL2 (18 feet): the chip’s internal oscillator circuit output.
2, reset circuit In the microcontroller system, the reset circuit is very critical, when the program runs (not running normally) or dead (stop running), it is necessary to reset. MCS-5l series microcontroller reset pin RST (pin 9) appears more than 2 machine cycles of high level, the microcontroller performs a reset operation. If RST is continuously high, the microcontroller is in a cyclic reset state.
3, EA/VPP (31 pins) function and connection 51 microcontroller EA/VPP (31 pins) is the internal and external program memory selection pin. When EA stays high, the microcontroller accesses the internal program memory; when EA stays low, it only accesses the external memory regardless of whether there is an internal program memory.