[NTLK] Newton USB Dongle

[Matthias Melcher]

> On Feb 7, 2017, at 4:20 PM, Randy Glenn <randy.glenn at gmail.com> wrote:
> 
> On Mon, Feb 6, 2017 at 3:16 PM, Matthias Melcher <mm at matthiasm.com> wrote:
> 
>> I have found a perfect programmable logic chip that can interface the ESP
>> to the internal port including the required level shifting, also adding SD
>> Card support, keyboard emulation vie WLan, and NTK and Inspector support.
>> All we need is the ESP, the FPGA, a PCB, and the connectors, optionally an
>> SD Card holder.
>> 
>> ...and time to plug it all together...
> 
> 
> Which chip is that?

I chose the CPLD Altera MAX 3000 series EPM3032. 

https://www.altera.com/content/dam/altera-www/global/en_US/pdfs/literature/ds/m3000a.pdf

The chip is small, but still solderable with my equipment. It tolerates the 5V logic in the Newton and controls the ESP32 at 3.2 Volts. Also it is very cheap (1.80 Euros in singles). Even if all I do is run the signals through it to only change from 5V to 3V and back, it is already a win.

It can be reprogrammed at any time without he need of an extra programmer. I could, for example, load a program into the ESP32 that completely reconfigures the connection between the ESP and the Newton, even after the board is already mounted inside the MessagePad. Firmware changes hardware. 

Did I mention that the ESP32 has a builtin low power Bluetooth stack? This thing has more calculating power than the entire MP ;-).

Would anyone be interested in writing the software (on the ESP and on the Newton) to make this work? If so, I should be able to sit down and make 10 or so boards for a few bucks. Everything will of course be OpenSource on my side.