headless setup

dpavlin@nuc:~/Downloads$ unzip 2020-08-20-raspios-buster-armhf-lite.zip

dpavlin@nuc:~/Downloads$ dd iflag=fullblock oflag=direct conv=fsync status=progress bs=1M if=2020-08-20-raspios-buster-armhf-lite.img of=/dev/sdb

dpavlin@nuc:~/Downloads$ sudo mount /dev/sdb1 /mnt/sdb1/

# enable ssh
dpavlin@nuc:~/Downloads$ sudo touch /mnt/sdb1/ssh

# configure wifi
dpavlin@nuc:~/Downloads$ sudo cp /tmp/rpi4-backup/wpa_supplicant.conf /mnt/sdb1/

dpavlin@nuc:~/Downloads$ cat /mnt/sdb1/wpa_supplicant.conf
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=HR

network={
	ssid="wifi_ssid"
	psk="wifi_password"
	key_mgmt=WPA-PSK
}

dpavlin@nuc:~/Downloads$ sudo umount /mnt/sdb1
dpavlin@nuc:~/Downloads$ sudo eject /dev/sdb

PCF8591 8-Bit A/D D/A Converter Module

AIN0 - Jumper P5 - Light Dependent Resistor (LDR)
AIN1 - Jumper P4 - Thermistor
AIN2 - Not connected
AIN3 - Jumper P6 - Potentiometer

RaspberryPi

pi@raspberrypi ~ $ grep snd /etc/modprobe.d/raspi-blacklist.conf 
blacklist snd-bcm2708

pi@raspberrypi ~ $ grep i2c /etc/modules
i2c_dev


pi@raspberrypi ~ $ sudo i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- UU -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- -- -- -- -- UU -- -- -- -- 
40: -- -- -- -- -- -- -- -- 48 -- -- -- -- -- -- -- 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: -- -- -- -- -- -- -- --                         


pi@raspberrypi ~ $ gpio -x pcf8591:120:0x48 readall
+------+---------+--------+
|  Pin | Digital | Analog |
+------+---------+--------+
|  120 |     0   |   132  |
|  121 |     0   |   224  |
|  122 |     0   |    89  |
|  123 |     0   |   119  |
+------+---------+--------+
pi@raspberrypi ~ $ gpio -x pcf8591:120:0x48 aread 120
132
pi@raspberrypi ~ $ gpio -x pcf8591:120:0x48 aread 121
224
pi@raspberrypi ~ $ gpio -x pcf8591:120:0x48 aread 122
99
pi@raspberrypi ~ $ gpio -x pcf8591:120:0x48 aread 123
118

pi@raspberrypi ~ $ gpio -x pcf8591:120:0x48 awrite 120 128

References

• http://embeddedprogrammer.blogspot.com/2012/07/hacking-ov7670-camera-module-sccb-cheat.html

RaspberryPi

• http://nicolasfley.fast-page.org/?page_id=35

FPGA

• http://hamsterworks.co.nz/mediawiki/index.php/OV7670_camera
• https://github.com/ahmadabbas55/miniOV7670

Stereo vision

• http://danstrother.com/2011/06/10/fpga-stereo-vision-core-released/
• http://code.danstrother.com/dls_cores/