From ae9130ee8f8d78dd7b1b121a15145db46f39377f Mon Sep 17 00:00:00 2001 From: Alex Tereschenko Date: Sun, 7 Jun 2015 09:56:37 +0200 Subject: [PATCH 1/1] edison.md: corrected ADC resolution data Edison kit for Arduino has TI ADS7951 ADC, which has "12-stored-in-16" bit resolution. Signed-off-by: Alex Tereschenko Signed-off-by: Brendan Le Foll --- docs/edison.md | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/docs/edison.md b/docs/edison.md index 2815057..7e15df8 100644 --- a/docs/edison.md +++ b/docs/edison.md @@ -23,8 +23,10 @@ in libmraa: - Max SPI speed is 25Mhz/4 ~6.25Mhz - SPI PM can sometimes do weird things you can disable it with: `echo on > /sys/devices/pci0000\:00/0000\:00\:07.1/power/control` -- ADC kernel module will return 12bit number but the ADC itself only has an - accuracy of 10bits. This ADC is only included on the Arduino board. +- ADC kernel module will return 16bit number but the ADC itself only has an + accuracy of maximum 12bits and in MRAA it's limited to 10bits by default. + Use `mraa_aio_set_bit(12)` to switch to the maximum resolution mode. + This ADC is only included on the Arduino board. - AIO pins are treated as 0-5 in `mraa_aio_init()` but as 14-19 for everything else. Therefore use `mraa_gpio_init(14)` to use A0 as a GPIO - Arduino pin 7 can sometimes negatively impact the WiFi capability, if using -- 2.7.4