NumWorks open source calculator

[Hubert Weikert]

Got my device yesterday, and looked 'under the hood'...

(08-29-2017 03:57 PM)mfleming Wrote:  The last page of the schematics indicate connectors for QUADSPI, USART, SPI and microSD. No mention is made of any of these connectors on the web site, so I'm sure they're not populated . . . but could be?

What is called USART (U7) is a 64 Mbit flash memory, wired for QuadSPI. The pads for are on the board, same as for the microSD (U8) with resistor/FET (R15/Q4), all of them are not populated.

(08-29-2017 03:57 PM)mfleming Wrote:  The processor supports USB OTG, but the USB ID pin is left floating (pity!) so it can only be used in device mode. I wonder if the pin is brought out to an appropriate TP?

All five USB pins are available directly at the USB connector. So it may be possible to connect the respective microcontroller pin to the USB connector with a very thin wire.

I made some pictures of the board, they are available at Pictures Calculator

Hubert