I've prepared a draft of the design of the new and greatly enhanced Y-Box. Schematics:
http://downloads.qi-hardware.com/people/werner/anelok/tmp/ybox-draft-20140116.pdf Layout: http://downloads.qi-hardware.com/people/werner/anelok/tmp/ybox-draft-20140116.png Changes from the old version: - added KL25 (for USB) and CC2543 (BTLE-capable RF SoC) - PCB is now 45.1 x 21.6 mm = 974 mm^2 (up from 30.0 x 18.5 mm = 555 mm^2) - slot-mounted USB A receptacle should reduce overall case height by about 4 mm General features: - Freescale KL25 with 48 MHz ARM Cortex M0+, 128 kB Flash, 16 kB RAM, basically the same chip as in Anelok, but in a smaller package (32-QFN instead of 48-QFN) (1) - TI CC2543 with (I think) 32 MHz 8051 core, 32 kB Flash, 1 kB SRAM, and a 2.4 GHz transceiver that's assumed (2) to be BTLE-capable - general layout (see the layout image, link above, for details): 12 o'clock: PC-facing USB Micro B port. PC provides power to Y-Box and all that is attached. PC accesses the KL25 for RF communication. (3) 3 o'clock: device-facing USB A (full-size) receptacle. Device receives power from PC. 6 o'clock: Anelok-facing USB Micro B port. Anelok receives power from the PC and acts - through the Y-Box - as USB host for the device in the USB A receptacle. 9 o'clock: antenna. - two brightness-matched LEDs (green for the KL25 and red-orange for RF) on PWM-capable I/O pins - 5 general-purpose test pads on the KL25, 2 on the CC2543. Pads are 2 mm and each group (4+1+2) is placed with 1.2 mm spacing (which is roughly the spacing of ribbon cables) - large test pads on the bottom with >= 4 mm center-to-center spacing give access to power and in-circuit programming interfaces of both chips. (4) - KL25 has access to in-circuit programming signals of the RF SoC - single-crystal design: the RF SoC has the crystal and provides a precision clock (required for USB) to the KL25. (5) (1) May switch to a KL24/KL25/KL26 with smaller memories in the final product. The "big" chip is for development. (2) The chip is not marketed as BTLE-capable but its capabilities suggest that it can be used for it. Some low-level functionality that is usually done in hardware, e.g., whitening, may have to be done by software. (3) If all we need is power, the "PC" can be any USB power source. (4) To be used for a yet-to-be-designed "bed of nails" production programming device. (5) Since the CC2543 may have bad firmware, we cannot rely on it to provide the clock on its own. Therefore, the idea is that the DFU boot loader in the KL25 will reset the CC2543 and put it in debug mode, then command it to output the clock, enumerate, wait briefly for "emergency repair" DFU activity, and then jump to the application which can release/reboot the CC2543. Since the Y-Box is now considerably more complex than before, I've given it its own repository: https://gitorious.org/anelok/ybox The analok/ybox repository should be placed at the same level in the directory hierarchy as the anlok/anelok repository (and all the Qi-Hardware repos we use.) I plan to make a first board during the next week, so there is still plenty of time to review schematics and layout. After that the firmware has to be written (both for KL25 and CC2543) and finally the case design will have to be adapted, too. Once correct operation of the Y-Box is verified, Anelok will switch to the CC2543 (along with its firmware), too. Comments ? - Werner _______________________________________________ Qi Hardware Discussion List Mail to list (members only): [email protected] Subscribe or Unsubscribe: http://lists.en.qi-hardware.com/mailman/listinfo/discussion
