CPU

CPUID to arch: https://github.com/mer-tools/oprofile/blob/master/libop/op_hw_specific.h#L119
CPU flags meaning: http://unix.stackexchange.com/questions/43539/what-do-the-flags-in-proc-cpuinfo-mean

Endianness

https://www.cs.umd.edu/class/sum2003/cmsc311/Notes/Data/endian.html
In big endian, you store the most significant byte(MSB) in the smallest address.
In little endian, you store the least significant byte(LSB) in the smallest address

Protection ring

UEFI Shell

https://software.intel.com/en-us/articles/uefi-shell

map # list disks
help bcfg

Buses

VESA (Video Electronics Standards Association)

https://en.wikipedia.org/wiki/List_of_device_bit_rates

|Technology|Rate||Year| |—|—|—| |ISA 16-Bit/8.33 MHz|66.7 Mbit/s|8.33 MB/s|1984 (created)| |I²C|3.4 Mbit/s|425 kB/s|1992 (standardized)| |Low Pin Count|125 Mbit/s|15.63 MB/s [x]|2002| |HyperTransport 3.1 (3.2 GHz, 32-pair)|409.6 Gbit/s|51.2 GB/s|2008| |Unified Media Interface 2.0 (UMI 2.0; ×4 link)|20 Gbit/s|2 GB/s [z]|2012| |Direct Media Interface 3.0 (DMI 3.0; ×4 link)|40 Gbit/s|4 GB/s [z]|2015| |AGP 8×|17.066 Gbit/s|2.133 GB/s|2002| |AGP 8× 64-bit|34.133 Gbit/s|4.266 GB/s|| |PCI 32-bit/66 MHz|2.133 Gbit/s|266.7 MB/s|1995| |PCI 64-bit/100 MHz|6.4 Gbit/s|800 MB/s|| |PCI-X QDR|34.133 Gbit/s|4.266 GB/s|| |PCI Express 2.0 (×32 link)[43]|160 Gbit/s|16 GB/s [z]|2007| |PCI Express 3.0 (×32 link)[44]|256 Gbit/s|31.51 GB/s [y]|2011| |QPI (9.6GT/s, 4.8 GHz)|307.2 Gbit/s|38.4 GB/s|2014|

https://en.wikipedia.org/wiki/NVLink

Infini Band

https://en.wikipedia.org/wiki/InfiniBand

SDR DDR QDR FDR10 FDR EDR HDR NDR XDR
Signaling rate (Gbit/s) 2.5 5 10 10.3125 14.0625[6] 25.78125 50 100 250
Theoretical effective throughput, Gbs, per 1x[7] 2 4 8 10 13.64 25 50
Speeds for 12x links (Gbit/s) 24 48 96 120 163.64 300 600
Encoding (bits) 8/10 8/10 8/10 64/66 64/66 64/66 64/66
Adapter latency (microseconds)[8] 5 2.5 1.3 0.7 0.7 0.5
Year[9] 2001,2003 2005 2007 2011 2011 2014[7] 2017[7] after 2020 future

Raspberry PI

/opt/vc/bin/vcgencmd measure_temp

Console

/dev/ttyAMA0

Speed (baud rate): 115200
Bits: 8
Parity: None
Stop Bits: 1
Flow Control: None

Resolution

SQCIF = 128x96
QCIF = 176x144
QVGA = 320x240
CIF = 352x240/288
HVGA = 640x240
VGA = 640x480
2 CIF = 704x240/288
4 CIF = 704x480/576
D1 CROPPED = 704x480/576
D1 = 720x480/576

D1 (525) 720 x 480 is in NTSC
D1 (625) 720 x 576 is in PAL

720p is 1280 x 720. (921,600 total pixels)
1080p is 1920x1080. (2,073,600 total pixels)
3MP is 2048 x 1536. (3,145,728 total pixels)
5MP is 2560 x 1920. (4,915,200 total pixels)

Screen

Name Wiki
OLED https://en.wikipedia.org/wiki/OLED
microLED, micro-LED, mLED or μLED https://en.wikipedia.org/wiki/MicroLED
Mini LED https://en.wikipedia.org/wiki/LED-backlit_LCD#Mini_LED