Hello Embedia69,
Is it possible to program the chip by USB or is it possible only with SPI?
Answer: The first programming must be done through SPI, by “BlueFlash” tool. If you will create a application with bootloader support, then you can setup to support later firmware upgrade by UART or USB. So the answer is NO you cannot use the USB as a main programming method, it is used only for the end user. The main way for programming is the SPI connection. If you do not have LPT for programming, then you can use USB to SPI convertor for programming.
In the project options I can choose as transport layer “USB” does it means I can program by USB?
Answer: No. This options is used to select which hardware for communication you will use UART or USB. If you use USB then you cannot use at the same time the UART. For USB communication you will need to install required drivers also.
And in those options I can select the firmware, do I can program the bluetooth chipset with any firmware?
No. only the firmware which is suitable for the chip. If is single chip you need OEM CSR firmware if it is on Casira Development board you will need Casira CSR firmware.
Kind Regards,
electronix79