Magnitude Comparator

[Flipsyde412]

I have a problem how to configure the pin from my magnitude comparator ic. Because i don't know which pin i would choose from A3 B2 A2 A1 B1 A0 B0 B3. From the output coming from the 74194. Any suggestion would really help thx.. i attaching the pin diagram of 74ls85 try to check it out.

" If thats true so my 74194 pin output which is QD,QC,QB,QA where QD is my MSB and QA is LSB. Correct me if I'm wrong so therefore my 74194 pin output QD,QC,QB,QA = A3,A2,A1,A0 of 7485 where A3 is the MSB - LSB order. Therefore also if I will connect a new 194 to the 'B' section it will be the same as the first one i did but only that it will be B3,B2,B1,B0. Thx for the hp on me(help)

Also i got this newer problem i supposedly connect the 7485 output to my 74192 below it only I found out that 7485 only have 3 output pins while my 74192 needs 4 input to make if work so that its output can be display to my 7-segment common anode. How can i make my 7485 output be displayed in my 7-segment using my 74192? Also I'm uploading her a 74192 pin diagram just try to check it out. I'm just curious whats the difference between and 74LS192 than a 74192..because the pin name is quite differ in such a way though.

 

[Hero999]

You've got me thinking now.

Aren't inputs normally numbered from the least to most significant bit?

 

[ericgibbs]

hi,

Usually the 7485 requires two, 4 bit bin/bcd inputs to 'A' and 'B'.

You can connect your 74194 to either A or B, and the other input from another 74194 or hardwire/switch the pins.
Just remember to use the correct magnitude output sense.


The LSB's are the A0,B0 inputs thru to MSB's A3,B3.

Does this help ?
More info if you need it.

EricG

EDIT:
hi AllVol,
The OP should now have sufficient information to meet his query. I hope he lets us know!.
Thanks once again for the support.
Eric

 

[AllVol]

Not to step on Eric's toes, but he DID force me to study this chip a couple of days ago during a similar thread.

The 74ls85 compares two separate 4-bit words, or numbers, coming from two different sources, such as counter, shift register, etc., including hard-wiring one number on the chip.

One 4-bit word is placed on the inputs A0 thru A3, with the LSB on A0.
The other word is placed on inputs B0 thru B3. After comparison, the result will appear as a high (1) on either OA<B, OA=B or OA>B depending on the condition.

Comparison of words greater than 4-bit can be accomplished by cascading 'ls85 as described in the data sheet.

Hope this helps to clear some of the muddle.

How'd I do, Eric?