Storing bit flags and BCD lookup data in Ruby - ruby

Question

I'm writing a CLI that interacts with an external USB device. The device's status is discovered by reading the Status registers, 24x 8 bits wide. The register values are read from a serial port and arrive as an array of Strings:
=> ["000", "000", "000", "000", "086", "003", "000", "000", "255", "255", ...]
The registers are in 2 formats, bit flags and BCD (I'm not sure of Correct terminology here). They can be mix also.
Bit flags
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Error 10
Error 11
Error 12
Error 13
Error 14
Error 15
Error 16
Error 17
A value of 34 (0b00100010) means 'Error 16' and 'Error 12' are present.
BCD
Bit 2
Bit 1
Bit 0
result
0
0
0
State A
0
0
1
State B
0
1
0
State C
0
1
1
State D
1
1
1
State E
A value of 3 (0b00000011) means 'State D'
Is there an elegant Ruby way (or conventions) for storing and looking up this type of String data?

Answer 1

Although I don't quite understand what's the relation between the 24*8 Status registers and Bit flags and BCD, but I think it's just about the number base conversion.
You can use to_s if you want to change the number base from 2 to 36.
5.to_s(2)
# => '101'
255.to_s(2)
# => '11111111'
36.to_s(36)
# => '10'
After you convert the number to binary, you can use rjust to supplement with the leading zeros.
5.to_s(2).rjust(8, '0')
# => '00000101'
Then you can use the index of the string to decide what is the status now.
For Bit flags, you can make a array of errors:
errors = ['Error 10', 'Error 11', 'Error 12', 'Error 13', 'Error 14', 'Error 15', 'Error 16', 'Error 17']
'034'.to_i.to_s(2).rjust(8, '0').chars.each_with_index.map do |bit, index|
bit == '1' ? errors[index] : nil
end.compact
# => ["Error 12", "Error 16"]
For BCD you can make a Hash variable for the states:
states = {
'000' => 'A',
'001' => 'B',
'010' => 'C',
'011' => 'D',
'111' => 'E',
}
bits = '003'.to_i.to_s(2).rjust(8, '0')[-3..-1]
states[bits]
# => 'D'
btw, your markdown tables don't display well...