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Two HW UARTs

Posted: 24 May 2011, 8:19 AM
by dlh
Don,

On chips that have two high-speed HW UARTs, would it be possible to use either for downloading to the chip?

I am playing with a design where one UART can be switched between an FT232RL USB chip and a LAN (wired or wireless). The ethernet hardware can be plugged into the main board by the user so there might be instances where they don't want to use ethernet and are too far away from a PC to use USB (e.g. when the unit is in a wiring closet). In that case, it would simplify things if the second UART could be used for a PC link.

Re: Two HW UARTs

Posted: 24 May 2011, 8:57 AM
by dkinzer
dlh wrote:On chips that have two high-speed HW UARTs, would it be possible to use either for downloading to the chip?
It is not possible with the current version of the ZX bootloaders. It might be possible to modify the bootloader so that the downloading UART is somehow selectable.

Re: Two HW UARTs

Posted: 24 May 2011, 9:04 AM
by dlh
dkinzer wrote: It might be possible to modify the bootloader so that the downloading UART is somehow selectable.
If it is a major undertaking, never mind. There's always sneakernet to cover my (possibly rare) scenario. :wink:

I can interface with RS232 on the second port (with a cross-over adapter) for everything except downloading so normal operation would not be affected. They would just need to move it close enough to the PC to download via the USB link.