On this page, I will introduce the encoder which changes the 8bits code into 3 binary bits.
As the input code, the code that only 1 bit is 1 out of the 8 bits is needed.
ERROR becomes 'H level ' when the code which doesn't suit this condition is input.

It outputs "000" when "00000001" is input.
It outputs "001" when "00000010" is input.
It outputs "010" when "00000100" is input.
It outputs "011" when "00001000" is input.
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Pin lock isn't specified.
As the device, it deals with CPLD(XC9536-PC44).

Source code and Explanation Fitting report

Operating state table

Input								Output
H	G	F	E	D	C	B	A	Q2 - Q0	ERROR
0	0	0	0	0	0	0	1	000	0
0	0	0	0	0	0	1	0	001	0
0	0	0	0	0	1	0	0	010	0
0	0	0	0	1	0	0	0	011	0
0	0	0	1	0	0	0	0	100	0
0	0	1	0	0	0	0	0	101	0
0	1	0	0	0	0	0	0	110	0
1	0	0	0	0	0	0	0	111	0
Other								xxx	1