Stargate 3DS - PCB and firmware

[SylverReZ]

Because I don't have appropriate probes (nor a hot air station), I haven't been able to connect to the Atmel SAM D11 SWD. I would expect those to be exposed as test points on the PCB, but I am unable to properly guess which is which.

Orienting the PCB with the USB port up and the Stargate 3DS logo right:

• It seems that the two test points closest to the USB port are USB 5V.
• The test point middle-right seems to be 1.2V UART, but I'm not sure what that UART is connected to.
• The two test points closest to the left of the Stargate 3DS logo seem connected together, but I'm not sure what they're for.
• The two test points in the left-down corner are GND. I'm not sure what the test point above them is for.

If anyone else knows more about those test points, I'd be interested. I sadly can't figure out more without more tools on my side (without destroying the flashcart, at least.)

I came across a new discovery in the last week. There's a built-in UART mode for the Stargate 3DS. If you hold both buttons whilst plugging in the USB cable into your computer, the LED will glow red and come up as a new device named "Microchip Technology, Inc. CDC RS-232 Emulation Demo". I haven't gotten thus far when attempting to connect it to the Microchip MPLAB IDE, but somebody will let me know.

 

[amomo]

I came across a new discovery in the last week. There's a built-in UART mode for the Stargate 3DS. If you hold both buttons whilst plugging in the USB cable into your computer, the LED will glow red and come up as a new device named "Microchip Technology, Inc. CDC RS-232 Emulation Demo". I haven't gotten thus far when attempting to connect it to the Microchip MPLAB IDE, but somebody will let me know.

See this post from earlier in the thread:

UPDATE 1
Atmel chip is related to USB communication.
It is connected to the two data pins of USB.

When connected to a computer using a micro USB cable, RGB(or Green) LED lights up and nothing happens.
If you hold down one of the buttons on the cartridge that is further away from the USB port while connecting the USB cable,
Red LED pops up and USB serial port appears on the computer.

I don't get any information from the serial monitor program.
I assume that if there is a program implemented, there must be a special command.
I don't know exactly what it is yet.

From having looked at a part of the Atmel SAM D11 firmware, it seems to be the one responsible for handling UART communications. I'm still not sure what the protocol or serial configuration is, but it seems to be responsible for writing to the firmware SPI flash and programming the FPGA SoC over SPI. Because I'm missing the other half, I have to rely on mostly guesses as to what's happening.

 

[SylverReZ]

From having looked at a part of the Atmel SAM D11 firmware, it seems to be the one responsible for handling UART communications.

*Mostly* responsible for JTAG communications in terms of flashing a new firmware. The SmartFusion 2 line (as well as the ProASIC 3) uses DirectC which allows for in-circuit JTAG programming, much like what the MT-Card does.

Here is a full documentation on it from Microchip's website (they own both Microsemi and Actel).