DreamCatcher

1 Specs (Version 2.03)
2 Setting up the OS
3 Startup the DreamCatcher with Armbian Distro
4 Hardware Details
5 Outernet Specific Applications
6 ADS-B reception using dump1090
7 Running the Dreamcatcher SDR from another System
8 Listen to FM broadcasts
- 8.1 Install necessary Software
- 8.2 Enable sound output through the 3.5mm TRRS connector

Specs (Version 2.03)

Setting up the OS

There are two OSs that you can use on the DreamCatcher.

Armbian: Standard ARM Linux OS based on Debian, Highly supported but does NOT have build in support for Outernet. This OS requires lots of tweaking to get up and going...; Armbian for DreamCatcher, V5.27

NOTE: The kernel in this version of Armbian cannot be updated with apt, there is an issue with the Device Trees that will brick the device. Before doing an apt upgrade, set a hold on the kernel packages like this:

sudo apt-mark hold linux-dtb-next-sunxi linux-headers-next-sunxi linux-image-next-sunxi linux-firmware-image-next-sunxi

Skylark: Os based on Busybox is read only and has the full Outernet system ready to go. This is the one to use if you want to play with outernet with no tweaking

Version 4.4

Skylark, for the Passive Antenna, Released May 14, 2017

Skylark, for the Active Antenna, Released June 22, 2017

Version 4.x

Skylark, for both Antenna Types, Released October 10, 2017

Burning the image to an SD Card

A microSD greater than 4GB in size is required.

Extract the image

It is compressed using "gzip.", many common Unzipping tools on your chosen OS can un-compress these.

Linux / OSx: gunzip [filename.gz]

Windows: use 7Zip

Write the image to the SD card

the best way to burn the SD card is by using etcher here---> https://etcher.io/

Startup the DreamCatcher with Armbian Distro

Show

1) Insert SD card into Dreamcatcher board slot marked "SD0_OS," next to LED array.

2) insert the USB Wifi Dongle, or other USB network device if you have it.

3) Optionally - connect the USB Cable to your PC with a terminal application open.

4) connect power to a USB port, or alternatively the USB cable to PC can provide power

after the bootup process you should see a "Dreamcatcher Login:" prompt

Default Username: root
Default Password: 1234

Configure Wifi

To connect to a wifi network, you can use one of the following methods, SSID/password will be stored and applied automatically at next boot.

Single Command Line

nmcli d wifi connect [your_ssid] password [your_password]

nmcli d wifi connect MYSSID password IMSOSECURE

if you succeed, you should see something like:

Connection with UUID '8f820c8a-5af3-4336-8161-6f57030a7ec5' created and activated on device 'wlan1'

Simple Command line Gui

nmtui

The UI is very self explanatory.

Check the current IP

to check assigned ip use:

ifconfig

root@dreamcatcher:/etc# ifconfig
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:8 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1104 (1.0 KiB)  TX bytes:1104 (1.0 KiB)

wlan1     Link encap:Ethernet  HWaddr e8:4e:06:4b:a6:fa  
          inet addr:10.0.1.150  Bcast:10.0.1.255  Mask:255.255.255.0
          inet6 addr: fe80::ea4e:6ff:fe4b:a6fa/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:78 errors:0 dropped:0 overruns:0 frame:0
          TX packets:41 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:14882 (14.5 KiB)  TX bytes:4947 (4.8 KiB)

Install The RTL-SDR Libraires and Utilities

To install librtlsdr and sdr utilities like rtl_fm etc, use:

apt update; apt install rtl-sdr

(you will need to have already connected to network for this to work)

Shutting Down

Unlike Skylark, the root filesystem here is modified and is writeable, so it is important you shut this down properly:

sudo poweroff

Hardware Details

Show

Documentation

AllWinner A13 Processor Datasheet

AXP209 Power Management IC Datasheet

Board LEDS

Onboard LEDs can be controlled by writing to the ON/OFF Control file in SysFs. In the case of LED1/Pckts to turn on the led, write a 1 to the SYSFS Device On/Off Control.

To Turn the Led on:

echo 1 > /sys/class/leds/packet/brightness

To Turn it off:

echo 0 > /sys/class/leds/packet/brightness

CHGLED
Description	Indicates LiPo Battery Charging
Color	Green
Default at Boot	OFF
SysFs Device
Usage
Notes	indicate LiPo charge if it was used, but as it also introduces noise to the system LiPo powering option was eliminated

LED1 / Pckts
Description	Flashes with Outernet Packets are Received
Color	Green
Default at Boot	OFF
SysFs Device	/sys/class/leds/packet
Usage	On/Off = brightness
Notes	Unused in Armbian

LED2 / Flock
Description	Satellite Lock Indicator on when satellite signal is locked
Color	Red
Default at Boot	OFF
SysFs Device	/sys/class/leds/lock
Usage	On/Off = brightness
Notes	Unused in Armbian

LED3 / SNR1
Description	SNR indicator
Color	Blue
Default at Boot	OFF
SysFs Device	/sys/class/leds/snr1
Usage	On/Off = brightness
Notes	Unused in Armbian

LED4 / SNR2
Description	SNR indicator
Color	Blue
Default at Boot	OFF
SysFs Device	/sys/class/leds/snr2
Usage	On/Off = brightness
Notes	Unused in Armbian

LED5 / SNR3
Description	SNR indicator
Color	Blue
Default at Boot	OFF
SysFs Device	/sys/class/leds/snr3
Usage	On/Off = brightness
Notes	Unused in Armbian

LED6 / SNR4
Description	SNR indicator
Color	Blue
Default at Boot	OFF
SysFs Device	/sys/class/leds/snr4
Usage	On/Off = brightness
Notes	Unused in Armbian

LED7 / USR1
Description	sdcard activity indicator. equivalent of the HDD activity light
Color	Green
Default at Boot	OFF
SysFs Device	/sys/class/leds/storage
Usage	On/Off = brightness
Notes

LED8 / USR2
Description	heartbeat: flashes when kernel is booted and working normally.
Color	Green
Default at Boot	OFF
SysFs Device	/sys/class/leds/heartbeat
Usage	On/Off = brightness
Notes	long off, N short flashes, long off, repeat, where N = 2 * Load_Average

LED9 / PWR
Description	Power: White LED, on when board is powered.
Color	White
Default at Boot	ON
SysFs Device
Usage
Notes

LED10 / AGP3
Description	Status indicator of Boot by default
Color	Red
Default at Boot
SysFs Device
Usage
Notes	AXP209.gpio2

LED11 / STATUS
Description
Color	Green
Default at Boot
SysFs Device
Usage
Notes	AXP209.gpio2

LED12 / USBH
Description	USB Hub Indicator Light, Green when active
Color	Green
Default at Boot	ON
SysFs Device	/sys/class/leds/usbhuben
Usage	On/Off = brightness
Notes	Turning this off, will disable all USB ports.

RF Ports

There are two RF ports on the DreamCatcher, they are labeled "LNA_IN" (at the corner of the board), and "LNA_BYPASS". They are SMA Type connections. To enable them you will write a 0 or a 1 to the appropriate SYSFS file location. Writing a 1 will enable it, and a 0 will disable it. if you enable one, you must disable the other;

NOTE: you must be a Superuser to control these... use "sudo su" first

Enable LNA_BYPASS

This is normally selected when you are using an external LNA, or Active Antenna

echo 1 > /sys/class/leds/rfswitch1/brightness
echo 0 > /sys/class/leds/rfswitch2/brightness

Enable LNA_IN

This would be used with a passive antenna or internal LNA

echo 0 >  /sys/class/leds/rfswitch1/brightness
echo 1 >/sys/class/leds/rfswitch2/brightness

Enable LNA_BYPASS Bias Tee

To Enable the bias tee, use the following commands

NOTE: 68 mA current limit set by R76/100k

echo 119 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio119/direction
echo 1 > /sys/class/gpio/gpio119/value

Enable Internal Audio Speaker Amplifier

sudo su
cd /sys/class/gpio
echo 114 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio114/direction
echo 1 > /sys/class/gpio/gpio114/value

Running “alsamixer”, turn up the volume (navigate with cursors, cursor up volume up) and un-mute all channels (pressing “m” key while cursor on them)

Speaker amplifier output vias near C42, C43:

Temperature Monitoring

Armbian includes a monitoring application that gives you access to some of the hardware level details... for example to determine the CPU Temp use the following command:

armbianmonitor -m

however this of little use in automated monitoring or application development.

Usage: armbianmonitor [-h] [-b] [-c $path] [-d $device] [-D] [-m] [-p] [-r] [-u]

############################################################################

 Use armbianmonitor for the following tasks:

 armbianmonitor -c /path/to/test performs disk health/performance tests
 armbianmonitor -d monitors writes to $device
 armbianmonitor -D tries to upload debug disk info to improve armbianmonitor
 armbianmonitor -m provides simple CLI monitoring
 armbianmonitor -p tries to install cpuminer for performance measurements
 armbianmonitor -r tries to install RPi-Monitor
 armbianmonitor -u tries to upload armhwinfo.log for support purposes

############################################################################

Direct access to System Values

Board Temperature

The following returns the temperature of the CPU in Celsius

cat /sys/class/thermal/thermal_zone0/temp

Returns:

This is the same as 32.9C

CPU Information

cat /proc/cpuinfo

Returns:

processor	: 0
model name	: ARMv7 Processor rev 2 (v7l)
BogoMIPS	: 858.75
Features	: half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpd32 
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x3
CPU part	: 0xc08
CPU revision	: 2

Hardware	: Allwinner sun4i/sun5i Families
Revision	: 0000
Serial		: 1625428a0703290a

Processor Features

half: Half Word loads and stores
thumb: Thumb (16-bit instruction set)
fastmult: 32×32→64-bit multiplication
vfp: VFP (early SIMD vector floating point instructions)
edsp: DSP extensions (the 'e' variant of the ARM9 CPUs, and all others above)
thumbee: ThumbEE
neon: Advanced SIMD/NEON on AArch32
vfpv3: VFP version 3
tls: TLS register
vfpd32: VFP with 32 D-registers

System Load Averages

cat /proc/loadavg

Returns:

0.96 0.79 0.75 1/115 19306

0.96 = Last One Minute CPU and IO Utilization

0.79 = Last 5 minute CPU and IO Utilization

0.75 = Last 10 minute CPU and IO Utilization

1/115 = Running processes / Total processes

19306 = Last process ID used

System Memory Usage

cat /proc/meminfo

Returns

MemTotal:         510684 kB
MemFree:           40648 kB
MemAvailable:     441480 kB
Buffers:          205240 kB
Cached:           191808 kB
SwapCached:            0 kB
Active:            87248 kB
Inactive:         342072 kB
Active(anon):      13624 kB
Inactive(anon):    18860 kB
Active(file):      73624 kB
Inactive(file):   323212 kB
Unevictable:           0 kB
Mlocked:               0 kB
HighTotal:             0 kB
HighFree:              0 kB
LowTotal:         510684 kB
LowFree:           40648 kB
SwapTotal:        251324 kB
SwapFree:         251324 kB
Dirty:                 0 kB
Writeback:             0 kB
AnonPages:         32308 kB
Mapped:            21816 kB
Shmem:               212 kB
Slab:              25540 kB
SReclaimable:      15144 kB
SUnreclaim:        10396 kB
KernelStack:         936 kB
PageTables:          892 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:      506664 kB
Committed_AS:     182860 kB
VmallocTotal:     507904 kB
VmallocUsed:           0 kB
VmallocChunk:          0 kB
CmaTotal:          65536 kB
CmaFree:             648 kB

MemTotal: Total amount of physical RAM, in kilobytes.
MemFree: The amount of physical RAM, in kilobytes, left unused by the system.
Buffers: The amount of physical RAM, in kilobytes, used for file buffers.
Cached: The amount of physical RAM, in kilobytes, used as cache memory.
SwapCached: The amount of swap, in kilobytes, used as cache memory.
Active: The total amount of buffer or page cache memory, in kilobytes, that is in active use. This is memory that has been recently used and is usually not reclaimed for other purposes.
Inactive: The total amount of buffer or page cache memory, in kilobytes, that are free and available. This is memory that has not been recently used and can be reclaimed for other purposes.
HighTotal and HighFree: The total and free amount of memory, in kilobytes, that is not directly mapped into kernel space. The HighTotal value can vary based on the type of kernel used.
LowTotal and LowFree: The total and free amount of memory, in kilobytes, that is directly mapped into kernel space. The LowTotal value can vary based on the type of kernel used.
SwapTotal: The total amount of swap available, in kilobytes.
SwapFree: The total amount of swap free, in kilobytes.
Dirty: The total amount of memory, in kilobytes, waiting to be written back to the disk.
Writeback: The total amount of memory, in kilobytes, actively being written back to the disk.
Mapped: The total amount of memory, in kilobytes, which have been used to map devices, files, or libraries using the mmap command.
Slab: The total amount of memory, in kilobytes, used by the kernel to cache data structures for its own use.
Committed_AS: The total amount of memory, in kilobytes, estimated to complete the workload. This value represents the worst case scenario value, and also includes swap memory.
PageTables: The total amount of memory, in kilobytes, dedicated to the lowest page table level.
VMallocTotal: The total amount of memory, in kilobytes, of total allocated virtual address space.
VMallocUsed: The total amount of memory, in kilobytes, of used virtual address space.
VMallocChunk: The largest contiguous block of memory, in kilobytes, of available virtual address space.

TODO: I want to see how the RPi-Monitor works on the DreamCatcher, i know it works on the RaspberryPi and the OrangePi

Powering the Board Without a USB Cable

You can power the DreamCatcher with 5v to the JP1 current sense option jumper (+) and any convenient ground point such as the ground pin on the CHG-IN header.

Additional Headers

SPI1
Description	Serial Peripheral Interface
MOSI	Master Output, Slave Input
MISO	Master Input, Slave Output
CS0	Slave Select
CLK	Clock
GND	Ground

SPI2
Description	Serial Peripheral Interface
MOSI	Master Output, Slave Input
MISO	Master Input, Slave Output
CS0	Slave Select
CLK	Clock
GND	Ground

TWI2
Description	Two Wire Interface (I2C)
GND	Ground
3V3	3.3 Volt
SCK	Serial Clock Line
SDA	Serial Data Line

UART1
Description	Universal Asynchronous Receiver/Transmitter
GND	Ground
RX	Receive Line
TX	Transmit
3V3	3.3 Volt

JTAG
Description	Joint Test Action Group
RESET_N	Test Reset
GND	Ground
TDO	Test Data Out
TCK	Test Clock
TMS	Test Mode Select
TDI	Test Data In
3V3	3.3 Volt

GPIO
Description	These are in not in the correct order (what IS the CORRECT order?) Use the names to identify
5V0	5.0 Volt
GNDD1
PC15/NDQ7
PC13/NDQ5
PIN17/NRE
PC3/NCE1
PC1/NALE
PC19/NDQS
PG9/LED1
PG11/USBH
PE5
PB16
PB15
PE9
PE10
PE11
PB1
3V3
GNDD
GNDD2
PC14
PC4
PC2
PC0
PB10
PG10
PE4
PE6
PE7
PE8
PB4
PB3
PB2
PB0

Test Points

P1
Description

P4
Description

P7
Description

P5
Description

P3
Description

PWRON
Description

RESET
Description

AXPGP0
Description

AXPGP1
Description

AXPGP3
Description

AXPGP2
Description

NMI_N
Description

P11
Description

P12
Description

USBH_EN
Description

USB0_DRV
Description

SPK
Description

FACTORY
Description

LCD_020
Description

LCD_021
Description

LCD_022
Description

LCD_023
Description

LCD_CLK
Description

LCD_DE
Description

LCD_HSYNC
Description

LCD_VSYNC
Description

TPY2
Description

TPY1
Description

TPX1
Description

TPX2
Description

NON_REM1
Description

SDA
Description

SCL
Description

HS
Description

Outernet Specific Applications

Show

Outernet Overview

NOTE: Complete Outernet support is provided by the SkyLark Release above. If you just want to play with Outernet, then using that build is much easier. The details for software setup below are more more advanced Outernet usage, without needing SkyLark..

Outernet Broadcasts on L-Band satellite

Satellite Details
Satellite Name	Orbital Position	Coverage Area	Outernet Frequency	Symbol Rate
I-4 F3 Americas	98°W	North, South, and Central America, Pacific and Atlantic Oceans	1539.8725 MHz	4200
Alphasat	25°E	Europe, Africa, Middle East, East Asia, Atlantic and Indian Oceans	1546.2500 MHz	4200
I-4 F1 APAC	144.0°E	Asia, Australia, Pacific and Indian Oceans	1545.9525 MHz	4200

Adding a custom Frequency

From time to time the frequency used for the Outernet datastream will change. This is the proper workaround for adding a new custom frequency:

1) Connect by terminal to your Dreamcatcher using the "outernet" user account

2) Open this config file with VI editor with "Sudo", edit then save: "sudo vi /mnt/conf/etc/skylark_config.json"; Enter the "outernet" user password when prompted for a password

3) Edit only the custom frequency and symbol rate setting (every other will change back on reboot)

"custom": {
     "label": "Custom",
     "value": "custom",
     "freq": "1546.25",
     "symbolrate": "4200"
}

4) Set the Outernet application to use the custom frequency: Open the "Tuner" Application; Select the "Satellite" tab

"Select "Custom" from the dropdown

ONDD Setup

FTP to a DreamCatcher, copy the following files off of the system... be SURE to FORCE binary transfer.

/usr/sbin/ondd(md5:207723be33f4da57bd64a6549e11e95d)
/usr/sbin/ontimeout (md5:5092f17f0152ca352799290999ba7a6c)

Create an empty conf file

/etc/ondd/ondd.conf

Create a place to place downloads

/home/downloads (or wherever)

Create a place for download cache

/home/download_cache

Run ondd with the following command:

/usr/sbin/ondd -d --pid_file /var/run/ondd.pid --cfg-gile [empty cfg file you created] -c [location for download cache] -o [location for completed downloads] -D /var/run/ondd.data --sdr-timeout-handler /usr/sbin/ontimeout

Command Help

[Skylark][outernet@outernet:/usr/sbin]$ /usr/sbin/ondd -h
00:11:21.099 [main] Unable to load config: /etc/ondd.conf (null)
Usage: ondd 
--cfg-file CONFIG_FILE override default config file location
--pid-file PID_FILE override default pid file location
--ctrl-sock SOCK_FILE override default control socket path used for ipc
--status-sock SOCK_FILE override default status report socket path - status e
--cert-file CERT_FILE override default ceritificate file location
-D SOCK_FILE data socket path to which the demodulator sends raw s
--sdr-timeout-handler script to execute if no data arrives through the date
-o PATH path to output directory where downloaded files are d
-c PATH path to cache directory where partially downloaded fd
-O PATH if specified, files which path does not begin with td
-b N set the maximum number of download completion eventsy
-d start ondd in daemon mode
-i print to stdout the current signal strength and snr,d
-V enable verbose mode
-v display ondd version info
-h display this helptext

External API Access

Skylark has 3 known access points for external api access. These APIs provide access to specific items in a JSON format. They do not require login and are enabled by default as far as we can tell (version 4.4)

getTunerStatus

This provides the tuner connection status which is the same as what is available in the ui under Tuner-->Status tab.

Access URL

http://10.0.0.1/DIRECT/getTunerStatus

The following values are provided:

getTunerStatus Values
JSON Parameter	Description	Example Value
error	Indicates by TRUE or FALSE if there was an error in processing the request	false
result	contains the complete parameter value set	(see below)

getTunerStatus "result" Parameter Values
JSON Value	Description	Example
event		"packet_received"
event_details
lock	Indicates the status of the satellite lock where: 0 = Not Locked 1 = Locked	1
freq	Frequency the receiver is tuned to.	1539.87
freq_offset	The frequency offset in Hz from the Primary frequency
set_rs
rssi	Received signal strength indication (dBm)
snr	Signal to Noise Ratio	Indicates the strength of the incoming signal to the device, must be higher than 3.0 to 4.0 for a quality locked signal
ser	Symbol Error Rate	The rate of error for the received packet stream
crc_ok	The number of packets that passed the CRC check	317628
crc_err	The number of packets that failed the CRC check	0
alg_pk_mn	This describes how much the signal stands out from the noise.	28.06
state	Indicates the current signal lock state, where: 0 = Search 1 = Signal Detect 2 = Const Lock 3 = Code Lock 4 = Frame Lock	4
transfers	This is a JSON Array that contains the current transfers in progress. Although this is usually just one item, the code clearly supports multiple simultaneous downloads	(See Below)

getTunerStatus "result" --> "Transfer" Parameter Values
JSON Value	Description	Example
carousel_id
path	File path for the download object
hash
block_count
block_received
complete

example JSON:

{
	"result": {
		"event": "packet_received",
		"event_details": "",
		"lock": 1,
		"freq": 1539.87,
		"freq_offset": -2557.35,
		"set_rs": 4200,
		"rssi": -116.74,
		"snr": 11.58,
		"ser": 0,
		"crc_ok": 317628,
		"crc_err": 0,
		"alg_pk_mn": 28.06,
		"state": 4,
		"transfers": [{
			"carousel_id": 2,
			"path": "opaks/58d9-news-pack.2017-09-05_1743.tbz2",
			"hash": "bb4d85e4e41c190780b67dc44aee2add2be413137f6aee0c197052281a8c902d",
			"block_count": 225,
			"block_received": 136,
			"complete": 0
		}, {}]
	},
	"error": false
}

Duplicating the UI Tuner Status

the UI tuner status provides some values that must be calculated from the API Values provided above.

Implementing the Tuner UI Values
UI Label	API Value(s)	Calculation
SNR (dB)	snr	snr
Lock	lock	lock? "yes" : "no"
Rssi (dBm)	rssi	rssi
APkMn Ratio	alg_pk_mn	alg_pk_mn
Frequency (MHz)	freq	freq
Freq Offset (Hz)	freq_offset	freq_offset
Symbol Error Rate (SER)	ser	ser
Packets Received	crc_ok, crc_err	crc_ok + crc_err
Valid Packets	crc_ok	crc_ok
Valid packets %	crc_ok, crc_err	round(100*crc_ok / (crc_ok + crc_err)
Packet Error Rate (PER)	crc_err, crc_ok	round(1000*crc_err/ (crc_ok + crc_err) ) / 1000
Lock State	state	0=Search, 1=Signal Detect, 2=Const Lock, 3=Code Lock, 4=Frame Lock
Transfers:	path, block_received, block_count	path + (round( 100 * block_received / block_count)) + "%"

getAPRS

This interface provides a complete listing of the received APRS messages.

Access URL

http://10.0.0.1/DIRECT/getAPRS

getTunerStatus Values
JSON Value	Description	Example
result
error

example JSON:

{
	"result": "KE7WWT-1>APMI01,TCPIP*,qAS,KE7WWT:OUTNET\n
  KE7WWT-1>APMI01,TCPIP*,qAS,KE7WWT:OUTNET\n
  KE7WWT-1>APMI01,TCPIP*,qAS,KE7WWT:OUTNET\n",
	"error": false
}

whatsNew

provides a list of the whats new listing

Access URL

http://10.0.0.1/DIRECT/whatsNew

getTunerStatus Values
JSON Value	Description
result	Complete result set, separated by "\n" between rows
error

Example JSON:

{"result":
	"1504634234,combined.js\n
 	1504634005,Amateur Radio/APRS/APRSAT/messages-2017-09-05_17:53.txt\n
 	1504633409,News/2017-09-05.EurekAlert - Breaking News.NASA sees development of Tropical Depression 19W.html\n
 	1504633409,News/2017-09-05.EurekAlert - Breaking News.Opioid abuse can be treated successfully in primary care settings, stud.html\n
 	1504633408,News/2017-09-05.EurekAlert - Breaking News.Eating meat linked to higher risk of diabetes.html\n",
 "error":false}

Running Custom Scripts

The Skylark release for the DreamCatcher is a read only system. Although there are logs and data written to certain locations, you cannot install additional applications on the system with tools such as apt and yum. You can however, run scripts at boot that may be used to start other services as needed.

Since version 1.2 Skylark has support for starting a user script at bootup. For the technically inclined, look at /etc/init.d/S99user, that should tell you all.

Installing User Boot Script

first become root: sudo su -
then make a directory called bin in /mnt/conf: mkdir /mnt/conf/bin
in this directory create your script and call it user.sh: vi /mnt/conf/bin/user.sh

as an example, heres a script that logs the snr every 10 seconds

#!/bin/sh

while true
do
	a=$(wget -q -O - http://127.0.0.1/DIRECT/getTunerStatus | jq .result.snr)
	echo -n $(date) ": "
	echo $a
	sleep 10
done >> /mnt/downloads/snrlog.txt

make sure the script is executable, and owned by root: chown root:root /mnt/conf/bin/user.sh; chmod 755 /mnt/conf/bin/user.sh

NOTE: be careful though:

The script is run at the end of boot. So if you make changes to any service files or configs, you should restart that service as well. Be careful about how much RAM and CPU you consume in this script. Its a very limited system.

ADS-B reception using dump1090

Show

Install Updates and Base Packages

sudo apt-mark hold linux-dtb-next-sunxi linux-headers-next-sunxi linux-image-next-sunxi linux-firmware-image-next-sunxi 
sudo apt update
sudo apt upgrade
sudo apt install rtl-sdr librtlsdr-dev pkg-config build-essential
wget https://raw.githubusercontent.com/keenerd/rtl-sdr/master/rtl-sdr.rules
sudo mv rtl-sdr.rules /etc/udev/rules.d/

Reboot the DreamCatcher

sudo reboot

Install dump1090

Download and compile dump1090 (one time only):

mkdir adsb
cd adsb
git clone https://github.com/MalcolmRobb/dump1090
cd dump1090
make

Antennas

Hook-up a 1090MHz antenna, suitable for ADS-B reception to the LNA_BYPASS RF input of Dreamcatcher. You can find some good starting points here: http://discussions.flightaware.com/ads-b-flight-tracking-f21/three-easy-diy-antennas-for-beginners-t20177.html

Running dump1090

echo 1 | sudo tee /sys/class/leds/rfswitch1/brightness
echo 0 | sudo tee /sys/class/leds/rfswitch2/brightness
./dump1090 --interactive --net

NOTE: The “rfswitch1” and “rfswitch2” lines are not strictly necessary, but will not hurt anything - the Dreamcatcher Armbian image ships with the LNA bypass enabled by default.

Running dump1090 as a daemon

if you dump1090 to run in the background after a reboot, you need to set it up as a daemon.

Create a Startup script in /etc/init.d

The following is a sample startup script. This was poached from this site: http://www.satsignal.eu/raspberry-pi/dump1090.html

Create a simple script in /etc/init.d, in my case i called it, dump1090.sh
Cut and paste the following into the file

#!/bin/bash
### BEGIN INIT INFO
#
# Provides:		dump1090
# Required-Start:	$remote_fs
# Required-Stop:	$remote_fs
# Default-Start:	2 3 4 5
# Default-Stop:		0 1 6
# Short-Description:	dump1090 initscript

#
### END INIT INFO
## Fill in name of program here.
PROG="dump1090"
PROG_PATH="/home/pi/dump1090"
PROG_ARGS="--interactive --net --no-fix --net-ro-size 500 --net-ro-rate 5 --net-heartbeat 60 --gain -10"
PIDFILE="/var/run/dump1090.pid"

start() {
      if [ -e $PIDFILE ]; then
          ## Program is running, exit with error.
          echo "Error! $PROG is currently running!" 1>&2
          exit 1
      else
          ## Change from /dev/null to something like /var/log/$PROG if you want to save output.
          cd $PROG_PATH
          ./$PROG $PROG_ARGS 2>&1 >/dev/null &
          echo "$PROG started"
          touch $PIDFILE
      fi
}

stop() {
      if [ -e $PIDFILE ]; then
          ## Program is running, so stop it
         echo "$PROG is running"
         killall $PROG
         rm -f $PIDFILE
         echo "$PROG stopped"
      else
          ## Program is not running, exit with error.
          echo "Error! $PROG not started!" 1>&2
          exit 1
      fi
}

## Check to see if we are running as root first.
## Found at http://www.cyberciti.biz/tips/shell-root-user-check-script.html
if [ "$(id -u)" != "0" ]; then
      echo "This script must be run as root" 1>&2
      exit 1
fi

case "$1" in
      start)
          start
          exit 0
      ;;
      stop)
          stop
          exit 0
      ;;
      reload|restart|force-reload)
          stop
          start
          exit 0
      ;;
      **)
          echo "Usage: $0 {start|stop|reload}" 1>&2
          exit 1
      ;;
esac
exit 0

NOTE: You need to alter the PROG_PATH value to the location of your dump1090 application

Set the permission to executable
```
sudo chmod +x /etc/init.d/dump1090.sh
```
Install to the startup directories
```
sudo update-rc.d dump1090.sh defaults
```
If you want to remove it later
```
sudo update-rc.d -f dump1090.sh remove
```
Test Start the application
```
sudo /etc/init.d/dump1090.sh start
```
NOTE: If you want to stop it
```
sudo /etc/init.d/dump1090.sh stop
```

Verify that it is running

To verify that the application is running connect to the IP Address of the system and 8080 like

http://10.0.1.150:8080

you should see a map load..

Running the Dreamcatcher SDR from another System

Show

Listen to FM broadcasts

Show

Its possible to listen to standard FM broadcast radio using the Dreamcatchers SDR.

Install necessary Software

sudo apt install rtl-sdr sox

Enable sound output through the 3.5mm TRRS connector

alsamixer

Enable every column except the second and third by pressing “m” (for mute/unmute) when the column is selected. Use the keyboard left-arrow and right-arrow keys to move among the columns. For the second column, use up-arrow and down-arrow keys to adjust output volume. Be careful to not set it too high; if the column color changes to white, it has been set too high. Leave the third column muted.

You may have to reset theseAon every boot. Alternatively, you can save and restore them using: sudo /usr/sbin/alsactl store sudo /usr/sbin/alsactl restore

Connect a TRRS (tip-ring-ring-sleeve) headset cable - the kind you might use with an Android phone - to the 3.5mm connector on Dreamcatcher that is labelled “headphn”. This has 4 conductors - a “normal” set of headphones has 3.

Run this:

rtl_fm -f 104.7M -M fm -s 340k -A fast -r 32k -l 0 -E deemp | play -r 32k -t raw -e s -b 16 -c 1 -V1 -

More information about the various command line options is at the rtl_fm homepage at http://kmkeen.com/rtl-demod-guide/

Obviously, the most important one is the -f option for selecting the tuned frequency. You may also have to play around with the -s if the output is noisy. FM broadcasts tend to be quite powerful signals, and I have not needed an antenna for receiving any of the local stations, but in case of bad reception, just adding a sub-1M SMA cable at the LNA_BYPASS RF input of the Dreamcatcher should improve reception dramatically.

DreamCatcher

Contents

Specs (Version 2.03)

Setting up the OS

Version 4.4

Version 4.x

Burning the image to an SD Card

Extract the image

Write the image to the SD card

Startup the DreamCatcher with Armbian Distro

Configure Wifi

Single Command Line

Simple Command line Gui

Check the current IP

Install The RTL-SDR Libraires and Utilities

Shutting Down

Hardware Details

Documentation

Board LEDS

RF Ports

Enable LNA_BYPASS

Enable LNA_IN

Enable LNA_BYPASS Bias Tee

Enable Internal Audio Speaker Amplifier

Temperature Monitoring

Direct access to System Values

Board Temperature

CPU Information

Processor Features

System Load Averages

System Memory Usage

Powering the Board Without a USB Cable

Additional Headers

Test Points

Outernet Specific Applications

Outernet Overview

Adding a custom Frequency

ONDD Setup

Command Help

External API Access

getTunerStatus

Access URL

Duplicating the UI Tuner Status

getAPRS

Access URL

whatsNew

Access URL

Running Custom Scripts

Installing User Boot Script

ADS-B reception using dump1090

Install Updates and Base Packages

Reboot the DreamCatcher

Install dump1090

Antennas

Running dump1090

Running dump1090 as a daemon

Create a Startup script in /etc/init.d

Verify that it is running

Running the Dreamcatcher SDR from another System

Listen to FM broadcasts

Install necessary Software

Enable sound output through the 3.5mm TRRS connector

Navigation menu

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