Re: Protoneer Nano-Arm #ubitx

Jerry Gaffke
 

I got a Blue Pill with the 48 pin TQFP STM32F103 about a year ago, got it to speak Arduino just fine.
Of course, some Arduino libraries aren't ported, but it's a major step up from the Nano.
Blue Pill boards can be had for $2 each.

As I suggested a few posts back, if you build a board with the 64 pin TQFP STM32F103 you have a wide range
of processors to choose from.  From an ARM M0 core with 64k of flash and 8K of RAM  for $1 at quantity
up to an M4 core with 1024k of flash and 192k of RAM and floating point hardware for for $8.
All pin compatible, with 50+ pins of user IO.  
Here's the bottom end part:  https://www.mouser.com/datasheet/2/389/stm32f030f4-956260.pdf
and the top end:  https://www.mouser.com/datasheet/2/389/stm32f405rg-956214.pdf

Build our own board and we can choose our own processor frequency to avoid that 12mhz BFO,
and perhaps have the UART-to-USB connection happen in a cable so we don't 
normally have to deal with the 12mhz USB oscillator.

Though, in an attempt to stay on topic, I will admit that
it would be much easier to just buy the Protoneer.

Jerry, KE7ER




On Tue, Apr 24, 2018 at 02:08 pm, Kees T wrote:
The various STM "pill boards" sound promising and are --very-- cheap.....did you know there are 17 different STM32F103 products out there and the STM32F103C8 is one of the "simpler" chips. The chips themselves go from 36 pins to 100 pins. I see they all have a RTC.

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