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OLIMEX / NB-IoT

NB-IoT is LPWAN technology for IoT
GNU General Public License v3.0
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Cannot use 5V logic. Level shifter not working when jumper closed between 1-2 and open betwee 2-3 #7

Open ASL07 opened 4 years ago

ASL07 commented 4 years ago

Hi, I am using BC66 dev kit. I need to interface a 5V logic device. I have soldered the jumper between position 2 and 1 (VCCB), so now VCCB is supposed to be an INPUT, as per your documentation I have connected both 5V_EXT and VCCB to 5V.

Then, I am using a simple program which simply sets GPIO1 HIGH

Expected: GPIO1 Voltage is 5V (VCCB)

Actual: GPIO1 voltage is ~2.4V

If I leave VCCB unconnected (same jumper set-up), then GPIO1 is ~2.9V at high level

DanKoloff commented 4 years ago

I have soldered the jumper between position 2 and 1 (VCCB), so now VCCB is supposed to be an INPUT, as per your documentation

Did you cut the original connection between position 3 and 2?

ASL07 commented 4 years ago

Yes, I have only connected position 1-2, position 2-3 are disconnected