03 Jan 2016: EOMA68 15.6in Libre Laptop Prototype PCBs first boot
We have a successful first boot on the EOMA68 15.6in Libre Laptop Prototype PCBs. Demonstrated here is an EOMA68-A20 user-removable CPU Card, with a split 3 PCB design: main board (PCB1), embedded controller, power management, keyboard and touchpad board (PCB2), and power / battery charger board (PCB3). The split design is necessary due to the size of the laptop (15.6in LCD) as well as the need for PCBs to be at different heights on opposite sides of the case.
A USB-UART dongle is still hard-wired to PCB1 so that the EOMA68-A20 CPU Card's console can be accessed. PCB3 is to be replaced, the final design will use a TI bq24196 which is properly compliant with the USB-OTG Power Specification. PCB3 is therefore currently being used in a temporary configuration and is not providing sufficient current to provide the full 3 amps required to power the LCD, and the CPU Card, and the Audio all at the same time.
As explained in the video, an earlier revision (1.1) EOMA68-A20 CPU Card is being used for this demo, and, given that there is no PWM line on the revision 1.1 CPU Cards, the LCD Backlight has been hard-wired to permanently on at 100% brightness, resulting in maximum power draw for the backlight.
Despite the overcurrent draw resulting in a shutdown of the Power PCB, due to the temporary configuration of the power, the demonstration can be declared a success. Investigations will continue, and the casework will be 3D printed ready for when the replacement Chicony Keyboards arrive. The next demonstration will therefore be of a fully-assembled prototype laptop.