CH340

I have ESP32-Cams i’ve been trying to get working. After buying counterfiet FDTI interfaces I’m have little patience left. Will these cheapo CH340 cards program the ESP32Cam or any other MCU via TTL serial for that matter? I know the CH340 works with windows of this century… unlike the damn things on amazon.

https://www.aliexpress.com/item/32989224656.htm <<< OOOPS

Sorry - bad link… that’s a MCU! You know what I mean… tired… on wrong account… etc… here it is… third board mentioned…

Is this @mattlogue? You're only allowed to have one account here.

Mlogue9: After buying counterfiet FDTI interfaces I'm have little patience left.

What problem did you have with the counterfeit FTDI? If there is already a forum topic you created about that, you can just post a link to it.

I've been using the couterfeit FTDI exclusively with Windows for the last 7 years. There was a short time where the Windows driver "bricked" these counterfeits, but that was easy to work around. Soon after that, FTDI rethought there strategy and pushed a new driver update that no longer bricked the counterfeits. That was years ago and there have been no problems with the counterfeits since. I'm not defending the counterfeiters. I bought my FTDI adapters before it was widely known that the cheap ones on eBay, etc. were counterfeit, though the low price was certainly suspicious. But I also think it's important to clear up any misunderstandings that might result from outdated information about these modules.

Mlogue9: Will these cheapo CH340 cards program the ESP32Cam

My primary concern would be that these use 5 V logic levels, while the ESP32 uses 3.3 V. If so, you would need to use a logic level converter on the CH340 module's TX line to avoid damaging your ESP32.

Also note that you will need to manually enable uploading on the ESP32 to upload. It is possible to add an auto-reset circuit to avoid this, but the USB serial adapter module needs to break out the correct signal pins for that to be possible. More information here: https://youtu.be/ikhZ34WgObc?t=26

Mlogue9: or any other MCU via TTL serial for that matter?

I recommend you get one which uses the standard "FTDI header" pinout:

  • DTR or RTS
  • RX
  • TX
  • VCC
  • CTS
  • GND

That will allow you to plug the adapter right in to an Arduino Pro Mini, or many other boards that use this standard pinout. If you get an adapter with a non-standard pinout, you would need to use a mess of jumper wires to adapt it to the standard pinout. It's hard to tell from the pictures, but at least some of those adapters you linked don't even break out the DTR or RTS pin, without which you will need to manually reset the microcontroller at just the right time on every upload. I'd much prefer to have an adapter that has all the necessary pins, even if it's a little more expensive.

I've certainly used a CH340 to program Pro Minis and a couple of STM32 MCUs via serial.

Yes. My PC forgot sign-in and I used Google login. Mean to merge em.

Pert... I overlooked the part in description it says "works with Windows XP, 2000, ME, 95, 3.11 (LOL, JK)..."...

anyhow the card shows up as a serial device to PC just fine... It's just NOTHING happened when u attached a MCU to it, other than MCU powered up. I confirmed with terminal sw.

To enter the bootloader on ESP32 one has to pull GPIO0 low and reset the processor. The NodeMCU boards with onboard USB/Serial do this automagically using the DTR signal on the serial side (like e.g. Arduino Uno), but for the ESP32 Cam and an external USB/Serial without DTR, one has to do this manually with a jumper.

You simply cannot beat the Pololu USB AVR Programmer v2.1 for ease of use, quality and flexibility, at the price they are asking. It even gives you an extra serial port!

Pololu engineers are renowned for their product support.

mattlogue: Pert... I overlooked the part in description it says "works with Windows XP, 2000, ME, 95, 3.11 (LOL, JK)..."...

State of the art! I guess their documentation is a few years behind the times. I can say I've successfully used all three of those chips with Windows 10, as well as the real and counterfeit FTDI FT232.

mattlogue: anyhow the card shows up as a serial device to PC just fine... It's just NOTHING happened when u attached a MCU to it, other than MCU powered up. I confirmed with terminal sw.

What did you expect to happen?

jremington: You simply cannot beat the Pololu USB AVR Programmer v2.1 for ease of use, quality and flexibility, at the price they are asking.

That is an interesting product. I really like the automatic voltage level adjustment and that they used the standard FTDI pinout. I'm also a fan of the 2x3 ICSP header instead of using a 2x5 header that will never be needed for the common Arduino boards and having to wrangle a stiffer 10 conductor ribbon cable and an adapter to convert it to 2x3.

The price is very reasonable, though the combination of a cheapo USB to serial module and my beloved USBasp comes in at 1/2 that on eBay. Still, for a tool you will be using for years, spending an extra $3 to get the one you want is well worth while.

I don't have any experience with the STK500 programmers. The closest I've used is the Arduino as ISP, which is pretty good.

jremington: It even gives you an extra serial port!

That's the only part of it that would be useful to @mattlogue for this particular project, since the AVR ISP aspect of the device isn't much use for an ESP32. That said, if you're going to work with AVR chips to any great extent, it's definitely worth having an ISP on hand.

MrMark: To enter the bootloader on ESP32 one has to pull GPIO0 low and reset the processor. The NodeMCU boards with onboard USB/Serial do this automagically using the DTR signal on the serial side (like e.g. Arduino Uno), but for the ESP32 Cam and an external USB/Serial without DTR, one has to do this manually with a jumper.

thanks... I'll have to remember

BJHenry: I've certainly used a CH340 to program Pro Minis and a couple of STM32 MCUs via serial.

good I got one in a box... My PC died tho