Supplementary instructions for pyboardCN V2 using DFU upgrade

dcexpert

Supplementary instructions for pyboardCN V2 using DFU upgrade [Copy link]

 

 

It is the easiest and most convenient way to upgrade the pyboard using DFU. However, due to an oversight in the parameters of this board, some boards are not easy to enter the DFU mode. The reason is that this time a better quality TDK crystal is used, and its load capacitance is 10pf; in the past, ordinary domestic crystals were used, and the load capacitance used was 18pf. This time the crystal was replaced but the capacitor was forgotten to be changed. As a result, the crystal oscillation stability time will be longer after the system is reset, which exceeds the detection time of the internal DFU program (DFU can use any integer frequency between 4-26M, and HSI is used for judgment). If your pyboardCN also encounters this problem, you can refer to the following method. The most direct solution is of course to replace the capacitor, but first, time is a bit too late, and manual replacement is easy to affect the quality. To use a sentence that has been played badly by current mobile phone manufacturers, we also have a lot of scary black technology, and the problem can be solved without changing the hardware. The method is also very simple. First, connect the RST pin to 3V3 (the two pads on the upper right corner of the 8-pin connector at the bottom of pyboardCN V2). Then, open the terminal software, connect to pyboardCN V2, and enter the pyb.bootloader() command to enter DFU mode. During the upgrade process, keep RST and 3V3 connected and do not disconnect. You can also disconnect USB first, then connect BOOT0 and RST to 3V3 at the same time, and then connect the SUB line to enter DFU mode. After entering, BOOT0 can be disconnected from 3V3, but RST needs to remain connected to 3V3.

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This content is originally created by EEWORLD forum user dcexpert. If you want to reprint or use it for commercial purposes, you must obtain the author's consent and indicate the source

lising

Learn quickly!

star_66666

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孤立质子

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sacq

Hurry up and study first

jinxiang

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简简丨单单

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zy459994202

This issue is being fixed

zy459994202

I tried it and it entered the DFU state normally.

dcexpert

zy459994202 posted on 2019-5-23 10:32 I tried it and it entered the DFU state normally

The DFU detection time is relatively short, which caused this problem. If you encounter similar phenomena, you can also give it to everyone for reference.

zy459994202

dcexpert posted on 2019-5-23 11:10 The detection time of DFU is relatively short, which caused this problem. If you encounter similar phenomena, you can also give you a reference.

Although it has entered the normal state, it is still not possible to directly burn the official firmware. It will prompt that the information in the dfu firmware does not match the current development board = =. It is still reliable to convert it to hex and burn it. In addition, the official code can be directly compiled into dfu or hex and then burned to the nucleo and discover development boards, which can be burned and run normally.

dcexpert

zy459994202 posted on 2019-5-23 14:53 Although it has entered the normal state, it is still not possible to directly burn the official firmware. It will prompt that the information in the dfu firmware does not match the current development board = =, and...

dfu can be written. Some chips have bugs in dfu mode (encountered on STM32L4). After downloading, the data will be wrong and cannot run. Now most of them are normal.

wmh111

asdads

wmh111

Thank you, big man. Thank you, big man.

wmh111

Thank you, bro