In these days we are dealing with Synergy USB HS interface used to read and write files on a USB Pen drive.
Our board uses the S7G2 controller in the LQFP176 package and unfortunately it has a shortage of pins.For this reason, in the design phase we made some choices aimed at saving pins, resources and also costs.
To save a couple of pins compared to SK-S7G2, DK-S7G2 and PE-HMI cards, we have always kept the USB host connector powered.
Many months ago, before designing our board, we tried this solution by adding a USB host connector always powered to the SK-S7G2, as described in the following diagram.
This works regularly with a demo program derived from AN0239 which does not use the signals for power supply: the insertion and extraction of the Pen drive is recognized and the counter.txt file is read and written correctly.
Unfortunately our card does not work and even the insertion of the Pen drive is not recognized.
For a week we have been looking for the reason for these operating differences between the modified SK-S7G2 and our board but we have not found them yet.
Does someone have similar experience?Any suggestions are welcome.
Thanks in advance and best regards.MPGA
In reply to RobertoG: