mraa  2.0.0
Low Level Skeleton Library for Communication on GNU/Linux platforms
Intel(R) MinnowBoard Max / MinnowBoard Turbot

MinnowBoard MAX is an open hardware embedded board designed with the Intel(R) Atom(TM) E38xx series SOC (formely Bay Trail). The MinnowBoard Turbot is a backward compatible revision with performance and hardware improvements. https://www.minnowboard.org/learn-more/minnowboard-max-compatible-with-upgrades

For product overview and faq see https://www.minnowboard.org/faq

For technical details see https://www.minnowboard.org/board-viewer or the legacy board https://www.minnowboard.org/minnowboard-max

Supported Firmware

MRAA has only been tested with 64 bit firmware version 0.73 or later.

SPI

For SPI support you need to load the low_speed_spidev kernel module and that will create the /dev/spidev0.0 device node. MRAA only knows about this one SPI bus and no other.

Interface notes

The low speed I/O connector supported as per table below. This assumes default BIOS settings, as they are not dynamcially detected If any changes are mode (Device Manager -> System Setup -> South Cluster -> LPSS & CSS) them MRAA calls will not behave as expected.

The platform is chardev capable on newer kernels.

Documentation shows i2c on bus #5, ACPI shows it on bus #6, but driver uses bus #7.

MRAA Number Physical Pin Function Sysfs GPIO Notes
1 1 GND
2 2 GND
3 3 5v
4 4 3.3v
5 5 SPI_CS 220 SPI (via low_speed)
6 6 UART1_TXD 225 UART1
7 7 SPI_MISO 221 SPI (via low_speed)
8 8 UART1_RXD 224 UART1
9 9 SPI_MOSI 222 SPI (via low_speed)
10 10 UART1_CTS 227 GPIO
11 11 SPI_CLK 223 SPI (via low_speed)
12 12 UART1_RTS 226 GPIO
13 13 I2C_SCL 243 /dev/i2c-7
14 14 I2S_CLK 216 GPIO
15 15 I2C_SDA 242 /dev/i2c-7
16 16 I2S_FRM 217 GPIO
17 17 UART2_TXD 229 UART2
18 18 I2S_DO 219 GPIO
19 19 UART2_RXD 228 UART2
20 20 I2S_DI 218 GPIO
21 21 GPIO_S5_0 82 GPIO
22 22 PWM0 248 PWM Chip 0 Channel 0
23 23 GPIO_S5_1 83 GPIO
24 24 PWM1 249 PWM Chip 1 Channel 0
25 25 S5_4 84 GPIO
26 26 IBL_8254 208 GPIO / I2S MCLK (tb)

*(tb) New assignment on the MinnowBoard Turbot ** On 3.18+ kernels, sysfs GPIO numbers are computed using: new_value = old_value | 0x100

User LED

The MinnowBoard Turbot has one user programmable built-in LED. This is exposed as a GPIO from MRAA.

MRAA Number Physical Pin Function Sysfs GPIO Notes
27 N/A D2_LED 104 Active low