How to deal with disabled USB mode (HL78xx)

IoT Modules HL78
1

I made a mistake and disabled the USB mode (with AT+KUSBCOMP=0 and AT+CFUN=1,1) on a HL78xx while the UART port is not connected.
How do I recover?

The AT command manual mentions the USB mode is disabled by default, how can we control the HL78xx at all (e.g. for manufacturing tests)?

2

you can route out the UART1 for AT command.

3

I was afraid you’d say that… :grinning:
ok, so for my specific board I guess I have to fix it by talking to the UART1 port.

what about all the other boards that we produce and ship? If USB mode is disabled by default and we intend to use the USB mode only (UART1 is not connected) how can we control the HL78xx at all?

4

then how did you do that for your module before?

5

I don’t know, but I just asked my (manufacturing/HW) colleagues

6

Is there no order/product flavour/option to have the USB mode enabled by default?

7

probably you need to check with the distributor or your manufacturing colleagues