When attaching quectel ep06e modem to cn8 slot, it doesn’t detect anymore in openwrt (snapshot build), not in windows. Seems I fried two modems in r64 board. But when I attach wifi module to that cn8 port, it detects and works correctly. So, is it hardware or software issue? Now I have two bricked modems after bananapi board.
Can it be that the current required by the modem could not be supplied by the board which lead to lower voltage/brown-out of VCC (as that could explain the result)?
How much power do those modems require?
Supply Voltage Range 3.1–4.4 V, typ. 3.3 V
As two modems stopped working after putting them to r64, I think about hardware issue, but I don’t know how to check. Wifi module I checked doesn’t use all pins on mpcie slot, maybe this is the reason why it survives
In r64 schematic (page 10,section 12) there are pins 46-49 maybe higher than 3v3 (5v + resistor)
Does your card use these pins?
yes. It uses these pins. https://ds-blobs-3.cdn.devapps.ru/20204061/Quectel_EP06_Hardware_Design_V1.2.pdf but I have quite popular modem and I don’t see any notices about incompatibility with bananapi
i cannot access the file, seems it needs forum login, can you upload it to gdrive or similar?
does it expect 3v3 on these pins? or on which is a delta to the ~5V?
As I understand, these pins use 1.5-1.8v
@sinovoip any suggestion about this?
46 is defined as 1V8 powerdomain (LED_WPAN# ANTCTL3* DO Tunable antenna control) 47+49 are defined as PCM_DOUT/DIN (see no voltage) 48 1V5 but not connected
i guess problem here is pin 46
BPI-R64 is burning out 2 modems, that i have insert in cn8 slot. Quectel EP06-E on few seconds of work get very hot and not detected anymore in any device. Meig modem is getting very hot and then stop working after few minutes of work. Seems, that CN8 slot of that board with over-voltage BUG and burning out any modem inserted in this slot.
P.S. I think there is point of problem:
you mix r2 with r64 here…these are 2 different boards
but one post above yours i’ve wrote
modem-card above wants 1v8 on pin 46, but r64 seems like having 5v-resistor, which can be 3v3 and above
but basicly you have to compare r64 pinout with your cards pinout
Is there any way to fix that?
imho not that easy, if you find the resistor R228/R805 (or maybe bridge as it is 0R) you can cut it and add 1v8 from somewhere else to the pcie-slot side or use a voltage regulator which brings 5v down to 1v8), beware of the possible current needed on this line and 46+48 are bridged together.