# Raspberry Pi

The Raspberry Pi is an inexpensive and popular ARM based single board computer with digital & PWM GPIO, and i2c interfaces
built in.

The Gobot adaptor for the Raspberry Pi should support all of the various Raspberry Pi boards such as the
Raspberry Pi 4 Model B, Raspberry Pi 3 Model B, Raspberry Pi 2 Model B, Raspberry Pi 1 Model A+, Raspberry Pi Zero,
and Raspberry Pi Zero W.

For more info about the Raspberry Pi platform, click [here](http://www.raspberrypi.org/).

## How to Install

Please refer to the main [README.md](https://github.com/hybridgroup/gobot/blob/release/README.md)

We recommend updating to the latest Raspian Jessie OS when using the Raspberry Pi, however Gobot should also support
older versions of the OS, should your application require this.

## How to Use

The pin numbering used by your Gobot program should match the way your board is labeled right on the board itself.

```go
package main

import (
"time"

"gobot.io/x/gobot/v2"
"gobot.io/x/gobot/v2/drivers/gpio"
"gobot.io/x/gobot/v2/platforms/raspi"
)

func main() {
  r := raspi.NewAdaptor()
  led := gpio.NewLedDriver(r, "7")

  work := func() {
    gobot.Every(1*time.Second, func() {
      led.Toggle()
    })
  }

  robot := gobot.NewRobot("blinkBot",
    []gobot.Connection{r},
    []gobot.Device{led},
    work,
  )

  robot.Start()
}
```

## How to Connect

### Compiling

Compile your Gobot program on your workstation like this:

```sh
GOARM=6 GOARCH=arm GOOS=linux go build examples/raspi_blink.go
```

Use the following `GOARM` values to compile depending on which model Raspberry Pi you are using:

`GOARM=6` (Raspberry Pi A, A+, B, B+, Zero)
`GOARM=7` (Raspberry Pi 2, 3)

Once you have compiled your code, you can upload your program and execute it on the Raspberry Pi from your workstation
using the `scp` and `ssh` commands like this:

```sh
scp raspi_blink pi@192.168.1.xxx:/home/pi/
ssh -t pi@192.168.1.xxx "./raspi_blink"
```

### Enabling PWM output on GPIO pins

For extended PWM support on the Raspberry Pi, you will need to use a program called pi-blaster. You can follow the
instructions for pi-blaster install in the pi-blaster repo here:

[https://github.com/sarfata/pi-blaster](https://github.com/sarfata/pi-blaster)