I have a product I'm bringing to market. In the design, I'd like to give my customers the ability to upgrade the Propeller with new firmware simply using a Micro USB cable and a custom PC app. I think I should have no issues doing that part.
In my design, I plan on using a PIC18F27K42 micro controller. This PIC will control a graphical OLED and do some other functions for the device. Communications between the PIC and Prop will be through a dedicated UART (Not the UART/USB pins on the Prop). The Propeller will be the main application and will need firmware updates on a semi-regular basis.
I'd like to have the option to update the PIC. These are normally programmed using an ICD or PicKit. I would prefer to not require my customers to need a programmer.
From looking at the specs of the PIC, it looks like it's somewhat straight forward. You need to apply a programming voltage (5V, I think) to the MCLR/Vpp pin and take the ICSP CLK & DAT lines low. Then it should just be a process of sending down the new program and verifying the data.
My initial design will use a Parallax FLiP and use it's on board USB connector to communicate with my PC App for both sending down user data and reprogramming the FLiP with new firmware.
My question is, how hard would it be to allow the Propeller pass through a new program while it's connected to my application? I understand, I need to write the PC App and the ability.
From looking at a PicKit, it looks like it's just another PIC processor, so I think the Propeller, should also be able to do this.