Which pins are required for USB programming

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HansH
 
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Which pins are required for USB programming

Post by HansH »

Hi all

I have an electronic question regarding lines to program a microcontroller:

Which USB-pins are required for programming through the USB port of the microcontrollerboards?

Are that really only the 4 pins of the original USB:
1 VBUS +5 Volt .. (red)
2 D- ...... data- ... (white)
3 D+ ..... data+ ... (green)
4 GND .. 0V ....... (black)

best regards
Hans

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leafon
 
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Re: Which pins are required for USB programming

Post by leafon »

Yes.

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adafruit_support_mike
 
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Re: Which pins are required for USB programming

Post by adafruit_support_mike »

HansH wrote: Fri Jan 20, 2023 3:17 pm Are that really only the 4 pins of the original USB:
1 VBUS +5 Volt .. (red)
2 D- ...... data- ... (white)
3 D+ ..... data+ ... (green)
4 GND .. 0V ....... (black)
The D+/D- pair will work for 1Mbps and 12Mbps connections. Microcontrollers use a 12Mbps connection, so those are all you need.

The only other signal in a USB-2.0 connection would be the ID line, which is only used by USB-OTG.

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HansH
 
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Re: Which pins are required for USB programming

Post by HansH »

@adafruit_support_mike

Thank You for additional information
The only other signal in a USB-2.0 connection would be the ID line, which is only used by USB-OTG.
and I guess, this OTG feature is (1) not supported by most microcontrollers like ItsyBitsy and (2) would only be required, if I wanted to connect some periphery like an USB Stick or mouse or whatever, correct ?

best regards
Hans

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adafruit_support_mike
 
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Re: Which pins are required for USB programming

Post by adafruit_support_mike »

Yes.

The biggest issue is that you'd have to program the microcontroller to work as a USB host. That's possible, but would be an advanced project.

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