Thermal Printer V3.0

Reprinted from original project

The arduino library file needs to be updated.
Unzip the Mao meow machine modification library.zip and copy the BluetoothSerial folder in this folder to C:Users. Your username is AppDataLocalArduino15packagesesp32hardwareesp321.0.6libraries to overwrite it.
Back up the original BluetoothSerial folder before overwriting.

The schematic diagram is based on V1, with the addition of a button paper feeding function. Other changes
are unchanged. A new button, a resistor and a capacitor are added to the PCB. There are no other changes.
The program used in the folder is also based on the V1 version of the program, with the addition of a button paper feed function.

Note: Do not import and update the schematic diagrams and PCB diagrams on Lichuang EDA to avoid changes in the package that may cause circuit anomalies. Just use them directly.

Particularly important:
1. For esp32, be sure to buy the esp32 wrapper e type, either 4m or 8m. Other models have not been tested and cannot be guaranteed to be ok.
2. When uploading code, you need to use tweezers and other tools to ground the boot pin first, and then connect USB to TTL to power on. Otherwise, you will not be able to enter download mode and disconnect after uploading.

other:

1. Pay attention to purchasing components according to the schematic diagram, do not buy with one click, especially resistors and capacitors that are often mistakenly identified as other products.
The pt4056 in the picture is actually tp4056
. 2. Do not solder the FPC seat backwards.
3. BR8205 and others When purchasing through channels, be careful to buy 6p, do not buy 8p
4. If you use a 18650 or lithium battery with a protection circuit, do not weld the components of the battery protection circuit
5. The battery must not be connected reversely, otherwise the circuit may be burned. To prevent reverse connection, tp4056 can be replaced with tp4056x.
6. Don’t buy duplicate components. Just buy one buzzer. S8050 and S8050J3Y are the same thing.
7. If you use 186502p, you don’t need to buy the X8821WV-02K-N0SN terminal block. It is for the lithium battery pack.

8. SS34 diode, one end with the white wire is the negative electrode
9, pin header, only need to solder 4, 3.3V, GND, RX, TX
10, the components that need to be ordered should be replaced with other models of the same value as much as possible, and order time is uncertain

Here are some things that don’t match:

1u R0603, this is the capacitor 1uf, 0603 specification, not the USB header recognized by default.

330 R0603, this is a resistor, 0603 specification, not an inductor

3.3uh, this is a 3.3uh inductor. Look for an inductor with this value. Do not use the 22uh inductor that is matched by default. It is fundamentally different.

See HD video: esp32 demo

Welcome to like and collect

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20210915 update

1. Correct the schematic diagram. If the BOM of components is required, accessories can be made according to the schematic. Do not use the BOM of PCB. Except for the 18650 battery box, all other types will match and there will be no component errors. Some may be out of stock. You need to adjust the model of the same value yourself. (The PCB has not been changed because there are too many changes, and wiring and other problems will occur, so try not to move as much as possible. You can just build the PCB directly when making the board)

20210928 update

1. Added 3d shell

2. When purchasing components, you can directly refer to the content in "Lichuang Mall Shopping Cart Details.xls". There will no longer be problems such as type errors and duplications.