Table of Contents
Today I soldered revision B of the NeoCore Main board. This goes along with the keyboard.
The changes from previous are;
- Changed the outline of the board to make it sturdier.
- Moved the USB Type-C connector to the right side. This way it is closer to the memories that the USB and USB-to-SPI bridge is connected to.
- Changed 3.3V, 2.5V and 1.1V buck converters to Torex XCL239/240 with built-in inductor.
- Moved all reset and power management circuits to a GreenPAK programmable circuit. Power and Reset can come from on-board tactile switches, debug, or keyboard. The same is true for reset.
- Updated the circuit for USB 1.1 pull-ups.
- Changed the internal POD to the same connector as the external, althouth vertical.
- And some other minor issues fixed.
Below is a zoom-ed in photo where the emulator/debugger for the GreenPAK is shown.
The GreenPAK is a programmable little jewel from Renesas. It has both analog as well as digital parts. Counters, delay lines, 26 LUT and a SPI interface.
The device handles all of the housekeeping work. Reset and power on/off. Both from keyboard as well as two buttons on the main board during development. There is also a watchdog managed by the device.
Now. Lets test it!