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felis / USB_Host_Shield_2.0

Revision 2.0 of USB Host Library for Arduino.
https://chome.nerpa.tech
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Vbus and 5v + 3.3v #515

Open khalid5d3 opened 4 years ago

khalid5d3 commented 4 years ago

Hi. I am trying to connect usb host shield with NodeMCU. I cut the traces (both 3.3v and 5v) from vbus but when i use my multimeter to check the continuity between 3.3V pin and Vbus pad i still get connection. why is that ?

I am trying to power the shield using the 3.3v pin but would want the usb devices to use 5v that's why I cut the traces but no luck.

Q2: should I connect my NodeMCU SPI pins to the ICSP connections on the shield or can I use the pins on the side. If i should use the ICSP connections, where do I connect the SS ? and what logic level should I output ? high or low ?

Q3: when I get OSC did not start does that mean the MCU did not recognize the shield or the device ? (in other words, suppose everything is connected properly but not USB device is connected, would the OSC didn't start message appear ?)

Q4: Should I power the shield using the ICSP connections VCC and GND or the pins on the shield will power it ? because I checked the continuity between ICSP Vcc and 3.3v , 5v and it seems there is no internal connection.

thank you.

gdsports commented 4 years ago

Use a usb host shield mini board to avoid problems with 5V logic levels.

"OSC did not start" means the ESP8266 cannot communicate with the max3421e.