*** If I enter rainbow brightness (1-8) in the terminal I will get in the log
Nov 13 15:08:12 Turris_JB button_sync.sh[29575]: Brightness update using button to: 30
Nov 13 15:08:14 Turris_JB button_sync.sh[29575]: Brightness update using button to: 30
Nov 13 15:08:16 Turris_JB button_sync.sh[29575]: Brightness update using button to: 30
Nov 13 15:08:18 Turris_JB button_sync.sh[29575]: Brightness update using button to: 30
Similarly
1 > 30
2 > 63
3 > 94
4 >127
5 > 158
6 > 191
7 > 221
8 > xxxx nothing
But if I type rainbow brightness -p (1-255) in the terminal I get a log
Entered > in log
30 > 28 log periodically /2 sec
63 > 61 log periodically /2 sec
94 > 91 log periodically /2 sec
127 > 124 log periodically /2 sec
158 > 155 in the log with only one first entry
191 > 188 . . . – "–
221 > 219 . . . – "–
254 > 252 . . . – "–
255 > xxx . . . with no log entry
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Brightness 1 of the range 1-8 is too strong-bright, it is better to set more detailed brightness -p 5 starting from, for example, 5 and above.