#Getting started with CM Home board

<abstract>
This article explains how to get started with the CM Home board 
</abstract>

##What do you need to start ?

To start you need at least the following parts:

* A Raspberry Compute Module CM4S: <https://www.raspberrypi.com/products/compute-module-4s/> 
* a Hi-quality, Hi-speed, Hi-reliability microSD card like the [Industrial SanDisk available on our eshop](/pricelist?category=cmpanel)
* A 12VDC @ 1A or 24VDC @ 0.5A power supply like the [HDR-15-24](/pricelist?category=cmhome)
* An USB to 3.3 volt serial adapter like the [USB-3V-SER](/USB-3V-SER) 
* An Ethernet cable wired on a LAN with a DHCP server  

## Create a bootlable microSD 

Download the Raspberry Pi Imager from this url:

* <https://www.raspberrypi.com/software/>

then launch it.

<img src="./raspberry_pi_imager_1.jpg">

Press the <code>CHOOSE DEVICE</code> button and select <code>Raspberry Pi 4</code>

Press the <code>CHOOSE OS</code> button and select the Raspberry Pi OS you like. In this 
example we will use <code>Raspberry Pi OS (other)</code> -> <code>Raspberry Pi OS Lite (64-bit)</code> 

Insert in your PC the blank microSD and press the <code>CHOOSE STORAGE</code> button and select 
the microSD storage.

<img src="./raspberry_pi_imager_2.jpg">

Press the <code>NEXT</code> button.

<img src="./raspberry_pi_imager_3.jpg">

Press the <code>EDIT SETTINGS</code> button.

<img src="./raspberry_pi_imager_general.jpg">

In this form set the hostname of your CM Home, the user and password.

Switch to the tab <code>SETTINGS</code> and enable the SSH access.

<img src="./raspberry_pi_imager_services.jpg">

Press the <code>SAVE</code> button the the <code>YES</code> button.

<img src="./raspberry_pi_imager_3.jpg">

The <code>YES</code> again.

<img src="./raspberry_pi_imager_confirm.jpg">

At the end remove the microSD from your PC and insert it again. In this way a partition called 
<code>bootfs</code> will be mounted and we can make some changes on it.

Change the content of file <code>config.txt</code> with this:


	# For more options and information see
	# http://rptl.io/configtxt
	# Some settings may impact device functionality. See link above for details
	
	#Ignore the HDMI cable hotplug (to avoid the delay at startup)
	hdmi_ignore_hotplug=1
	
	# Set the debug port on GPIO32, GPIO33 pins
	force_turbo=1
	dtoverlay=uart1,txd1_pin=32,rxd1_pin=33
	
	# Enable the 1-wire bus
	dtoverlay=w1-gpio,gpiopin=16
	
	# Set the audio lines on GPIO40 and GPIO41 pins
	dtoverlay=pwm,pin=40,func=4
	dtoverlay=audremap,pins_40_41
	
	# Enable audio (loads snd_bcm2835)
	dtparam=audio=on
	audio_pwm_mode=2
	
	# Set the I2C1 on GPIO 44 and GPIO 45 pins
	dtoverlay=i2c1,pins_44_45
	
	#Enable the debug message
	enable_uart=1
	
	# Automatically load overlays for detected cameras
	camera_auto_detect=1
	
	# Automatically load initramfs files, if found
	auto_initramfs=1
	
	# Run in 64-bit mode
	arm_64bit=1
	
	# Run as fast as firmware / board allows
	arm_boost=1
	
	# Enable the LAN9514 chip
	dtoverlay=dwc2,dr_mode=host


Edit the file <code>cmdline.txt</code> changing <code>console=serial0,115200</code> in <code>console=serial1,115200</code>. 

Unmount the microSD card and insert it in its vertical socket

<img src="./microsd.jpg" class="img-responsive">

Insert the Raspberry CM4S on its vertical socket and gently press it until snaps 
into the final position as shown below:

<img src="./cm_vertical_socket.jpg" class="img-responsive">


Plug the Ethernet cable to a LAN with a DHCP server active: 

<img src="./cm_lan.jpg" class="img-responsive">

If you have an USB to serial adapter insert its pins as shown below to
have access to the serial console port. 

* @article='USB-3V-SER'

The serial setup is <b>115200,N,8,1</b> without 
software and hardware handshake.

<img src="./debug_port.jpg" class="img-responsive">

Connect the power supply lines in a range of 12 to 24 volt DC using the screw terminals as pictured below. 
The blue led will turn-on to indicate the power availability:

<img src="./power_supply.jpg" class="img-responsive">

On the serial console the boot messages will appear on your serial terminal emulator. If you
are not using a serial terminal check the led on the ethernet connector to see if there is any activities and try 
to reach your board from your PC by typing:

	ping cmhome.local

Open a SSH session to get the access to the Linux prompt

	ssh pi@cmhome.local
	Login: pi
	Password: <yourpassword>

<hr>

@include='adv_cmpanel'