How does one decode a 6 bit binary to 2 7 segment display?

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The discussion revolves around the challenge of displaying a 6-bit binary multiplication result on two 7-segment displays using only integrated circuits (ICs). Participants express concerns about the limitations of the 74LS48 decoder, which only handles single digits, and the high cost of using multiple ICs or complex logic gates. Suggestions include using binary to BCD conversion ICs or a ROM lookup table, although participants note that certain older ICs are no longer available. There is confusion about the project requirements, particularly the restriction to use only ICs and the associated costs compared to microcontrollers. The urgency of the project deadline leads to consideration of alternative components like the 74HCT series, despite initial restrictions.
AilingLore21
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So a 3 bit 2 input multiplier has a maximum of 6 bits and the max integer product is 49. Problem is I have no idea displaying it in 2 seven segment displays since the 74LS48 decoder only has 4 inputs and 7 output, only good for a single 7 seg. And we are required only to use ICs which is rather costly for us. I thought about using a multiplexer but that would be too costly since it would have a lit of AND gates.
 
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There are ICs doing binary -> BCD conversion. And they are certainly cheaper than hundreds of individual logic gates. That conversion is messy, there is no easy way of doing it.
 
How about using a ROM, look up table?
 
AilingLore21 said:
... And we are required only to use ICs which is rather costly for us. ...
I don't understand this requirement. Only ICs, as compared to what? Costly, compared to what (micro-controller? That's an IC also)? And why?

Is this homework, or an exercise, or an actual product design?
 
NTL2009 said:
I don't understand this requirement. Only ICs, as compared to what? Costly, compared to what (micro-controller? That's an IC also)? And why?

Is this homework, or an exercise, or an actual product design?
A group project. Our professor is strangely old fasioned. Anyway, I'm curious about ROMS. Do they need any IC connections?
mfb said:
There are ICs doing binary -> BCD conversion. And they are certainly cheaper than hundreds of individual logic gates. That conversion is messy, there is no easy way of doing it.
I thought 74LS48 ICs were Binary to BCD ones? Are there more?
 
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74LS48 is BCD to 7 segments for a single digit. You have to split up your 6 bit binary multiplication result to the two digits.
 
AilingLore21 said:
And we are required only to use ICs which is rather costly for us.

Can you elaborate on these points? If only using ICs a ROM like NTL2009 suggested or a CPU would be easiest and probably the CPU would be cheapest. Can you use the 74HCT series parts? They are much cheaper and require a smaller supply current.

BoB
 
mfb said:
74LS48 is BCD to 7 segments for a single digit. You have to split up your 6 bit binary multiplication result to the two digits.

I did some digging and found out using Binary to BCD method. Problem is the 85 ICs have been phased out for decades according to some forums. I'm trying to replicate it using a 4 bit adder IC (74LS83) and a comparator circuit gates so it adds 3 whenever the output goes beyond 4. I'm having no luck on Logisim whatsoever. Since the inputs are 6 bits, bit number 6 and bit number 5 goes into the 1st 74LS83? And should I add 3 to these 2 bit inputs on the first 83?

2009-03-21_21-13-25-859.png

The second image is the closest I could find but it's a BCD to Binary one:

binary-to-bcd-gif.18767.gif
 
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rbelli1 said:
Can you elaborate on these points? If only using ICs a ROM like NTL2009 suggested or a CPU would be easiest and probably the CPU would be cheapest. Can you use the 74HCT series parts? They are much cheaper and require a smaller supply current.

BoB

I'm not familiar with the 74HCT. Supposedly, we're not to use them but since the deadline is a week away, I'm seriously tempted to.
 
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