Electroenthusiast
Active Member
Digital electronics theory supports four distinct logic values (as defined in VHDL's std_logic):
* 1 or High, usually representing TRUE.
* 0 or Low, usually representing FALSE.
* X representing a "Conflict".
* U representing "Unassigned" or "Unknown".
* - representing "Don't Care".
* Z representing "high impedance", undriven line.
* H, L and W are other high-impedance values, the weak pull to "High", "Low" and "Don't Know" correspondingly.
Reference: en.wikipedia.org/wiki/Ternary_logic
I didnt understand the concept of X, Z, H, L & W
Where is "conflict used in VHDL" ?
I read about High Impedance state, but may i know where exactly it has practical appliaction? As in Wiki ... i question why should 'we use it(refer wiki)?'
And whats weak High(H) / weak Low(L) ? Where is its practical Apllication?
Whats the difference between Unknown U and Don't Know (W)?... i guess both are some; am i right ?
* 1 or High, usually representing TRUE.
* 0 or Low, usually representing FALSE.
* X representing a "Conflict".
* U representing "Unassigned" or "Unknown".
* - representing "Don't Care".
* Z representing "high impedance", undriven line.
* H, L and W are other high-impedance values, the weak pull to "High", "Low" and "Don't Know" correspondingly.
Reference: en.wikipedia.org/wiki/Ternary_logic
I didnt understand the concept of X, Z, H, L & W
Where is "conflict used in VHDL" ?
I read about High Impedance state, but may i know where exactly it has practical appliaction? As in Wiki ... i question why should 'we use it(refer wiki)?'
And whats weak High(H) / weak Low(L) ? Where is its practical Apllication?
Whats the difference between Unknown U and Don't Know (W)?... i guess both are some; am i right ?
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