Zoltan Hudak / mbedPi

mbed API for Raspberry Pi boards.

mbedPi

This is an attempt to implement a limited number of mbed APIs for Raspberry Pi single-board computers. The project was inspired by and based on the arduPi library developed for the Arduino by Cooking Hacks .

/media/uploads/hudakz/board01.jpg

Specifications

  • Chip: Broadcom BCM2836 SoC
  • Core architecture: Quad-core ARM Cortex-A7
  • CPU frequency: 900 MHz
  • GPU: Dual Core VideoCore IV® Multimedia Co-Processor
  • Memory: 1GB LPDDR2
  • Operating System: Boots from Micro SD card, running a version of the Linux operating system
  • Power: Micro USB socket 5V, 2A

Connectors

  • Ethernet: 10/100 BaseT Ethernet socket
  • Video Output: HDMI (rev 1.3 & 1.4)
  • Audio Output: 3.5mm jack, HDMI
  • USB: 4 x USB 2.0 Connector
  • GPIO Connector: 40-pin 2.54 mm (100 mil) expansion header: 2x20 strip providing 27 GPIO pins as well as +3.3 V, +5 V and GND supply lines
  • Camera Connector: 15-pin MIPI Camera Serial Interface (CSI-2)
  • JTAG: Not populated
  • Display Connector: Display Serial Interface (DSI) 15 way flat flex cable connector with two data lanes and a clock lane
  • Memory Card Slot: Micro SDIO

GPIO connector pinout

Zoom in /media/uploads/hudakz/mbedpi_pinout02.png

Information

Only the labels printed in blue/white or green/white (i.e. p3, gpio2 ...) must be used in your code. The other labels are given as information (alternate-functions, power pins, ...).


Building programs for the Raspberry Pi with mbedPi

I use Qt Creator for development, however you can use any other IDE available on the Raspberry Pi (e.g. Geany) if you like. For a quick try:

  • Install Qt and the Qt Creator onto your Raspberry Pi. Then create a new "Blinky" Plain non-Qt C++ Project as follows: /media/uploads/hudakz/newproject.png

  • Change the main code as below:

main.cpp

#include "mbedPi.h"

int main()
{
    DigitalOut  myled(p7);

    while(1) {
        myled = 1; // LED is ON
        wait(0.2); // 200 ms
        myled = 0; // LED is OFF
        wait(1.0); // 1 sec
        printf("Blink\r\n");
    }
}


  • Copy the mbedPi.zip file into your project's folder and unzip.
  • Add the mbedPi.h and mbedPi.cpp files to your project by right clicking on the "Blinky" project and then clicking on the "Add Existing Files..." option in the local menu:

    /media/uploads/hudakz/addfiles.png

    /media/uploads/hudakz/addfiles02.png

  • Double click on Blinky.pro to open it for editing and add new libraries by inserting a new line as follows:

    /media/uploads/hudakz/libs.png

  • Compile the project.

  • Connect an LED through a 1k resistor to pin 7 and the ground on the Raspberry Pi GPIO connector.

  • Run the binary as sudo (sudo ./Blinky) and you should see the LED blinking. /media/uploads/hudakz/mbedpi_run.png

  • Press Ctrl+c to stop running the application.

include/PinNames.h

Committer:
hudakz
Date:
18 months ago
Revision:
2:131555dc6fb7
Parent:
1:1f2d9982fa8c

File content as of revision 2:131555dc6fb7:

#ifndef _PIN_NAMES_H_
#define _PIN_NAMES_H_

typedef enum {
    // Not connected
    NC = (int)0xFFFFFFFF,

    // GPIO names
    gpio2       = 2,
    gpio3       = 3,
    gpio4       = 4,
    gpio5       = 5,
    gpio6       = 6,
    gpio7       = 7,
    gpio8       = 8,
    gpio9       = 9,
    gpio10      = 10,
    gpio11      = 11,
    gpio12      = 12,
    gpio13      = 13,
    gpio14      = 14,
    gpio15      = 15,
    gpio16      = 16,
    gpio17      = 17,
    gpio18      = 18,
    gpio19      = 19,
    gpio20      = 20,
    gpio21      = 21,
    gpio22      = 22,
    gpio23      = 23,
    gpio24      = 24,
    gpio25      = 25,
    gpio26      = 26,
    gpio27      = 27,

    // Rapsberry Pi pin names
    p3          = gpio2,
    p5          = gpio3,
    p7          = gpio4,
    p8          = gpio14,
    p10         = gpio15,
    p11         = gpio17,
    p12         = gpio18,
    p13         = gpio27,
    p15         = gpio22,
    p16         = gpio23,
    p18         = gpio24,
    p19         = gpio10,
    p21         = gpio9,
    p22         = gpio25,
    p23         = gpio11,
    p24         = gpio8,
    p26         = gpio7,
    p29         = gpio5,
    p31         = gpio6,
    p32         = gpio12,
    p33         = gpio13,
    p35         = gpio19,
    p36         = gpio16,
    p37         = gpio26,
    p38         = gpio20,
    p40         = gpio21,

    // Extension board V2.1 pin names
    P0          = gpio17,
    P1          = gpio18,
    P2          = gpio27,
    P3          = gpio22,
    P4          = gpio23,
    P5          = gpio24,
    P6          = gpio25,
    P7          = gpio4,
    CE1         = gpio7,
    CE0         = gpio8,
    CS          = gpio8,
    SCLK        = gpio11,
    MISO        = gpio9,
    MOSI        = gpio10,
    RXD         = gpio15,
    TXD         = gpio14,
    SCL         = gpio3,
    SDA         = gpio2,
    PWM         = gpio18,

    // Arduino pin names on the Extension board V2.1
    D2          = gpio18,
    D3          = gpio23,
    D4          = gpio24,
    D5          = gpio25,
    D6          = gpio4,
    D7          = gpio17,
    D8          = gpio27,
    D9          = gpio22
} PinName;

typedef enum
{
    PIN_INPUT,
    PIN_OUTPUT
} PinDirection;

typedef enum
{
    PullNone,
    PullUp,
    PullDown,
    OpenDrain,
    PullDefault = PullNone
} PinMode;

#endif	// _PIN_NAMES_H_