ADC_Precision

Very first notes

SD file system tools on Mac OS

usefull info on following link:

https://www.raspberrypi.org/documentation/installation/installing-images/mac.md

http://www.theinstructional.com/guides/disk-management-from-the-command-line-part-1

diskutil list

diskutil info /dev/disk1

diskutil unmount /dev/disk1s1

unmount single partition

diskutil eject /dev/disk1

copy all disk to raw partition

sudo dd bs=1m if=image.img of=/dev/rdisk<disk# from diskutil>

FAT-16 format

newfs_msdos -F 16 (path to SD Card device)/(SD Card device number)

e.g. newfs_msdos -F 16 /dev/disk5s1

diskutil partitionDisk /Volumes/WII 1 MBRFormat "MS-DOS FAT16" "WII" 1000M

Partition a disk with three partitions

diskutil partitionDisk disk3 3 HFSX Name1 10G JHFS+ Name2 10G MS-DOS NAME3 10G

l'ultima partizione viene estesa fino infondo quindi è necessario darne 1 fat16 e la seconda a piacere

altrimenti va in errore:

diskutil partitionDisk disk1 2 MBRFormat "MS-DOS FAT16" "WII" 1000M MS-DOS NAME3 1G

or

diskutil partitionDisk /dev/disk1 MBR "MS-DOS FAT16" "WII" 1000M MS-DOS NAME3 1G

diskutil unmountDisk /dev/disk<disk# from diskutil>

Take care to info in this blog and related

http://davidegironi.blogspot.com/2014/01/cheap-co2-meter-using-mq135-sensor-with.html#.W6fCIy2B3MW

and

https://automeris.io/WebPlotDigitizer/

AD converter precision

Lot of problem with AD voltage reference internal o r external too.

Solution

1 - using zenner diode 3 Volt (ITT ZPD 3) alone completely unusable

2 - using zenner and current source (PNP BC557)

3 - Using precision voltage reference TL431 .. the easiest one .. waiting from eBay ...