8 bit adc output to cascading bcd

[wejos]

hi guys,

is it possible to use this circuit from a 0804 output? i understand the output of the adc is 8 bit but how am i going to connect them to the bcd since it only has 4 inputs? should i connect the lsb to the second stage?

sorry if i'm trying to verify from you guys first before actually testing it. just trying to cut back cost here

**broken link removed**

thank you guys

 

[ericgibbs]

hi guys,

is it possible to use this circuit from a 0804 output? i understand the output of the adc is 8 bit but how am i going to connect them to the bcd since it only has 4 inputs? should i connect the lsb to the second stage?

sorry if i'm trying to verify from you guys first before actually testing it. just trying to cut back cost here

**broken link removed**

thank you guys

hi,
It depends upon the range and resolution you require in deciding to use the high or low nibble.

I dont see a circuit.?

 

[wejos]

https://www.edutek.ltd.uk/Graphics/Tutorials/BCD_Counter_4510/4510_multiple_counter_display.gif

that's the link to the url, Eric (source of schematic diagram)

i'm not sure i know about high or low nibble but i'm thinking at least three 7-segment display (upto 999)

 

[wejos]

idk what happened the website must have some kind of copy protection of their images. but i made a print screen and i hope they won't bother.

 

[ikalogic]

You need some circuit to convert your binary data (8 bit) to 3 BCD digits.
for example 219 (decimal) = 0b11011011 (binary) = 0010 0001 1001 (BCD)

 

[ericgibbs]

idk what happened the website must have some kind of copy protection of their images. but i made a print screen and i hope they won't bother.

hi,
As pointed out its a binary output from the 0804, the display driver require BCD inputs.

Logic Bin to BCD are not simple circuits, especially over a few decades.

 

[wejos]

You need some circuit to convert your binary data (8 bit) to 3 BCD digits.
for example 219 (decimal) = 0b11011011 (binary) = 0010 0001 1001 (BCD)

thanks ikalogic

the thing is i'm trying to avoid using pics and i'm sorry if no mention about that. it should be all hardware. truth is your suggestion gave me an idea how to implement this via software other than using truth table. first converting the binary to decimal then break them down to thre bcds. for the benefit of learning however i rather stick to hardware approach for now.

 

[wejos]

hi,
As pointed out its a binary output from the 0804, the display driver require BCD inputs.

Logic Bin to BCD are not simple circuits, especially over a few decades.

dear eric,

i reckon this schematic will not work for 8-bit input?

 

[ericgibbs]

dear eric,

i reckon this schematic will not work for 8-bit input?

hi,
The lower 4bit nibble of the 8bit output from the 0804, is from 00 to Fh, ie; 0 thru 15 decimal, if you connect this to a 7seg decoder IC you will only see 0 to 9 displayed, the A thru F binary values will be blanks.

This also applies to the upper nibble... sorry its a no go..

 

[wejos]

hi,
The lower 4bit nibble of the 8bit output from the 0804, is from 00 to Fh, ie; 0 thru 15 decimal, if you connect this to a 7seg decoder IC you will only see 0 to 9 displayed, the A thru F binary values will be blanks.

This also applies to the upper nibble... sorry its a no go..

now i am thinking to use pic

i'm always gracious for all your help guys, thank you for your time

i appreciate everything

 

[crutschow]

Read this.