Hexiwear etc

Reload Hexi firmware https://developer.mbed.org/questions/69735/HexiWear-Docking-Station-Firmware/?c=27761

Main Hx examples https://developer.mbed.org/teams/Hexiwear/code/ More from Hexiw https://developer.mbed.org/teams/Hexiwear/community/

K64 CPU Sleep

K64 - improved mbed sleep API https://developer.mbed.org/teams/SiliconLabs/wiki/Using-the-improved-mbed-sleep-API(part of interesting https://developer.mbed.org/teams/SiliconLabs/ )

best resource

• Wiki https://developer.mbed.org/users/mbed_official/code/mbed/docs/tip/, & mbed_sleep.h ...
• Sleep - mbed_sleep.h https://developer.mbed.org/users/mbed_official/code/mbed/docs/tip/mbed__sleep_8h_source.html
• or github https://github.com/ARMmbed/mbed-os/blob/master/platform/mbed_sleep.h

K64 Power Issues

For anyone looking for how to make the K64 mpu use less power, suggest you examine hal_deepsleep() which is in standard "mbed-os" and reduces mA to around 10mA for the entire Hexiwear from around 70mA. Unfortuinately you cannot then awaken it, so this is not a complete solution - - I resolved to add a tiny PIC that takes 1mA to provide the external awaken stimulus to save weeks / months going through their OS. Background - - for a so called low power mpu, it takes one heck of a lot (50mA to 70mA, which is way more than the screen) and the complexity in making it slow down is hideous - - one has to set semaphores (external timers and external interrupts etc) to awaken it from a deepsleep (standard sleep only saves about 50% if that). Apparently, you can set a watchdog, but no one from mbed / nxp or hexiwear has bothered to elucidate how to do that (and I rather think it is encumbent on them to do so as it is their mpu & os). So I leave this subject with a thought .. I really hope mbed-os is not going to be abandonware - - it started with huge promise and indeed you can do simple things with the hexiwear astonishingly quickly, but it is unfinished work .. needs more support.

Serial

Serial-LowPower-Demo Featured _{non hexi} https://developer.mbed.org/teams/SiliconLabs/code/Serial-LowPower-Demo/ (part of interesting https://developer.mbed.org/teams/SiliconLabs/code/ )

OLED bitmap tool

See https://developer.mbed.org/forum/team-4615-Hexiwear-community/topic/26474/