Access to USB port via backside pins?

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ikue

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Hi there,

I would like to use the "normal" USB function of Teensy 4.0 for serial communication.

The integrated micro USB female connector works fine if I connect a standard cable. Unfortunately, the available USB micro plugs take too much space and collide with other electronics.

My question: Is it possible to solder an own USB cable to D-, D+, GND and VIN and use the regular Serial.print by that line? This would save a lot of space, and is clearly the better option than trying to manually remove the existing micro USB female connector...

Thank you in advance!

Frederic
 
ikue said:
Hi there,

I would like to use the "normal" USB function of Teensy 4.0 for serial communication.

The integrated micro USB female connector works fine if I connect a standard cable. Unfortunately, the available USB micro plugs take too much space and collide with other electronics.

My question: Is it possible to solder an own USB cable to D-, D+, GND and VIN and use the regular Serial.print by that line? This would save a lot of space, and is clearly the better option than trying to manually remove the existing micro USB female connector...

Thank you in advance!

Frederic
Click to expand...

The pads you see under the Teensy are not the standard USB connector used by the micro-USB connector. These pads are for the HOST USB port that allows Teensy to acts as a separate USB host (similar to the USB HOST port brought out in the Teensy 3.6). Paul has said the reason the pads for the normal USB connection are not available are due to noise issues when the Teensy is running with a fast USB connection.

Whether it is simple to hook up the USB HOST connector to do what you want, I don't know.

One other option might be to use a USB to TTL serial connector, using one of the serial ports, such as:

<edit>
This breakout PCB is fairly minimal in its size requirements, bringing out a second row of pins on each side, and brings out the USB host pins in a form that you can use common cables:
 
Michael, this breakout board looks like just the thing I need. How would you solder the Teensy to the breakout board?
 
Note: That breakout brings out the HOST USB pins from the bottom. It does not extend the primary DEVICE USB from the Micro USB connector.

Only the T_4.0's device Micro USB has those pins used to program and do SerMon communication with the Teensy.

It still takes a cable - but there are cables to bring that out to a remote USB port.
 
PDOS said:
Michael, this breakout board looks like just the thing I need. How would you solder the Teensy to the breakout board?
Click to expand...

As I recall, I soldered a row of male pins on each side of the Teensy. You want to make sure there is enough room for the PCB board and for the pins to connect to what ever the Teensy connects with underneath (like a breadboard, protoboard, etc.). If you wanted to connect to the pins on the Teensy above it, you might want to use extra long male pins.

In theory you could use stacking headers, but with this setup, you would have to solder the stacking headers on top of the Teensy, and it can be hard todo.

Once you have a row of pins on each side, flip over the Teensy, and then solder the PCB board to the Teensy's outer pins, making sure the castellated holes line up with the solder pads.

You kind of have to glop the solder onto each of the castellated holes (hold the solder down at the pad, and bring the soldering iron in), and then check to see if the pin connects with the solder pad, using solder wick to clean up as necessary.

Because they are much smaller, the 8 1mm pads for the micro SD card are much harder to solder, making sure they connect and you don't have solder bridges.

I have a spool of thinner solder wire that is helpful with surface mount soldering, and for these PCBs.
 
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