HC-05 on hardware serial (answered)

Using Arduino Networking, Protocols, and Devices
1

I know it has to be disconnected to load a sketch. Quick question is, what must be disconnected? Is a switch on the HC-05 power line enough? On the RX? TX? Both? Project is still in planning stage awaiting HC-05 to arrive but want to plan out circuit and parts placement.
Thanks

2

A switch on the power line would suffice and a jumper bock would do just as well but, unless you intend to solder the module down, I'm not sure why you would bother doing this.

3

Thanks! The electronics will be in a housing and I will likely be upgrading and changing the program much more often than changing hardware. A USB cable can be routed out of the housing easily and a small switch is easier to install than opening the housing. Thanks for the reply and answer though.

4

Hello Joe.

I've just done some experimenting with a UNO and an HC-05.

Disconnecting just the HC-05's TXD pin (connects to the UNO's RX pin) is all that is needed to allow uploading a sketch.

I left the RXD/TX connection, the power and the ground connections in place. With the TXD/RX connection in place it will not upload.

So as I see it, a switch on the TXD/RX line would do the job. If you break the power supply that will kill the Bluetooth connection with the other device, which might be a slight inconvenience to you. Breaking the TXD/RX line would not kill the Bluetooth connection.

John.