Sourcing a CH341A

Cobrah

New member
Howdy, just ordered an FV-1 development board and the store was out of stock on CH341A chips. Anyone know where I can source one to get going with some FV-1 programming? I can only find ones that are part of an already soldered USB programmer. Might just get one of those and try and solder wick it off. Thanks to anyone that can help me find just the IC!
 

daeg

Active member
I had the same problem and ended up getting a Pythagoras, a CH341A USB programmer from Amazon, then superglued a 3.5mm TRS jack to it, and put another 3.5mm TRS jack into the Pythagoras enclosure and wired the jack up directly to the FV-1 chip.

Surprisingly, it worked perfectly.
 

mistersparkle

New member
I had the same problem and ended up getting a Pythagoras, a CH341A USB programmer from Amazon, then superglued a 3.5mm TRS jack to it, and put another 3.5mm TRS jack into the Pythagoras enclosure and wired the jack up directly to the FV-1 chip.

Surprisingly, it worked perfectly.
Pardon my ignorance, but I'm just in the early stages of educating myself on FV-1 programming. Can you elaborate a bit on your answer above? Like where do you connect the TRS jack on the CH341A programmer and where does it connect on the FV-1 (guessing SDA & SCL pins)? And what software do you use to dump programs, (i.e. the SpinAsm IDE, PedalPCB's AsProgrammer or some other utility)?
 

PedalPCB

Administrator
Staff member
You have to be careful hard wiring a USB CH341A programmer to the FV-1...

Most (all?) of those run on a 5V bus because the CH341A IC is powered directly by the USB port VBUS line. The FV-1 has a 3.3V maximum so while it might work you'd be overvolting the SDA/SCL lines.

The FV-1 Development Board only uses the data lines from the USB port, the CH341A IC is powered by an onboard 3.3V regulator.
 

mistersparkle

New member
You have to be careful hard wiring a USB CH341A programmer to the FV-1...

Most (all?) of those run on a 5V bus because the CH341A IC is powered directly by the USB port VBUS line. The FV-1 has a 3.3V maximum so while it might work you'd be overvolting the SDA/SCL lines.

The FV-1 Development Board only uses the data lines from the USB port, the CH341A IC is powered by an onboard 3.3V regulator.
Points well taken. I'd be happy to use the PedalPCB development board if I could find a reliable source for the CH341A chip, which seems to be "pure unobtainium" at the moment (unless you want to trust certain Asian-based vendors). Are those chips going to be available from PedalPCB in the future and/or do you have any experience with the legitimacy of the chips being sold by said Asian-based vendors?
 

daeg

Active member
Pardon my ignorance, but I'm just in the early stages of educating myself on FV-1 programming. Can you elaborate a bit on your answer above? Like where do you connect the TRS jack on the CH341A programmer and where does it connect on the FV-1 (guessing SDA & SCL pins)? And what software do you use to dump programs, (i.e. the SpinAsm IDE, PedalPCB's AsProgrammer or some other utility)?
Yep. You've got it. I hot-glued a Headphone Jack (2.5mm TRS) to one of the common CH341A programmers on Amazon, jumped 3 wires into were you'd normally put the EEPROM chip. Then on the Pythagoras I drilled a hole for another Headphone jack, and connected ground to ground, and the tip and ring to SDA & SLC pins on the board (can't remember which was which at the moment. I'll pull it apart and photograph it when I get a chance.)

At one point, I thought I fried my FV-1 with 5v, and even started a thread asking PedalPCB for help, but it turned out the CH341A programmer was only putting out 3.3V and my bad code was the problem.
 

mistersparkle

New member
yeah an eta on the CH341A would be amazing, I've been dreaming about the fv1 dev platform.
I'm going to take a gamble on the Asian vendor. I've had very good luck with them on quite a few things in the past, and it's only a couple, two/three bucks anyway. I'll let you know how it works out, keeping in mind that it might be two months till I get the part.
 

mistersparkle

New member
They all come from Asian vendors, I don't know of any US based suppliers.

I've never gotten a fake (or bad) one, but I've had a couple shipments never arrive.
Yeah, it's all about which vendor will supply legit parts in onesey-twosey quantities. Only been bit once so far with some fake MPF102 FETs. Wasn't a total loss though - they did test as good BJTs.:)
 

ITG6

Member
Howdy, just ordered an FV-1 development board and the store was out of stock on CH341A chips. Anyone know where I can source one to get going with some FV-1 programming? I can only find ones that are part of an already soldered USB programmer. Might just get one of those and try and solder wick it off. Thanks to anyone that can help me find just the IC!
Ran into the same problem. Bought two of the cheap programmers on eBay and used the chip from one of them. Put a small flathead screwdriver under the edge of the chip and heated the legs. Popped off pretty clean.
 

mistersparkle

New member
Coincidentally, I got two in the mail last week (luckily, not stuck in the Suez Canal), and I just finished my FV-1 Development Board a few minutes ago, plugged it into my laptop and bingo! Worked straight away. Fwiw, you might have to install one or more drivers, available here: http://www.wch.cn/download/CH341PAR_EXE.html I needed the driver to get my mini-programmer to work which also uses the CH341A chip, so I can't say for sure you'll need it for the PedalPCB device, but you probably will.
 
Last edited:

Bricksnbeatles

Active member
I ordered a few from AliExpress yesterday. I’ll report back if/when I get them
I got them yesterday and they appear to be legit. Fingers crossed (though I have no reason to doubt their authenticity since you can get CH341A dongle things for cheap anywhere, so the chips can’t be *that* rare
 

varlogtim

New member
Another option, albeit convoluted, is an Arduino. I have an old pedal I made with a headphone jack (tip: SDA, ring: SDL), and I plug this into a board with Arduino. I compile the FV-1 files and run a Python script which generates an Arduino code which writes to the EEPROM.

The Arduino can be detached when I want to put this on a board.

(this was prior to me finding pedalpcb.com so this thing is huge)

fv-1_pedal.png
 
Last edited:
Top