I am using a 08m2 pic-axe chip with a 4026 counter this is attached to a 7 segment (data sheet attached) I think I have everything wired up on a bread board but it does not work.
I am not sure where the ground goes from the 7 segment (I think it is pin 6), I am not sure also where pins 12, 9 and 8 should be wired up. I am using the 5C56-12 on the data sheet.
Can anyone help?
With the flow chart I am resetting the reset of the 4026 and turning off then turning output 2 on then off, it all works on the simulation but I am only using 1 seven segment.
Thanks
Mark

 

Assuming BC56-12 as the part under discussion,
Digit 1,2,3 are the common cathode type of seven segment displays.
Pin No. common cathode pin of Digit
12 --------------------->1
8 ---------------------->2
9 ---------------------->3
So, when the pin 12 is connected to Ground, the digit 1 is enabled and the number is displayed.
Similarly, connecting pins 8,9 will enable digits 2,3 respectively.
At any instant, only one of the digits should be enabled.
As it is mentioned that only one digit is being used,
connect pin number 12 to ground then the number will be displayed on the digit 1.
In the simulation, only one seven segment display is used with its common node connected to ground.
The 4026 should be given clock pulses.
I hope the explanation satisfies the doubt.

 

Assuming BC56-12 as the part under discussion,
Digit 1,2,3 are the common cathode type of seven segment displays.
Pin No. common cathode pin of Digit
12 --------------------->1
8 ---------------------->2
9 ---------------------->3
So, when the pin 12 is connected to Ground, the digit 1 is enabled and the number is displayed.
Similarly, connecting pins 8,9 will enable digits 2,3 respectively.
At any instant, only one of the digits should be enabled.
As it is mentioned that only one digit is being used,
connect pin number 12 to ground then the number will be displayed on the digit 1.
In the simulation, only one seven segment display is used with its common node connected to ground.
The 4026 should be given clock pulses.
I hope the explanation satisfies the doubt.

Thankyou for your reply, how can I write to all the segments of the 7 segment. So once the 4026 add up to 9 can it clock the second digit of the 7 segment or would I need another 4026?
Thanks
Mark

 

It is not possible with multiplexed displays like the 5c56-12.
The seven segment display shown in the data sheet is a multiplexed type of display.
In order to use a multiplexed seven segment display, the individual digits should be refreshed continuously.
It means that the digits should be enabled one after the other by giving the segment inputs (a to g) to each digit every time.

By using single seven-segment digits like the one used in simulation and one 4026 for each digit it is possible to cascade.
If the circuit has to show a two digit number, then one of the following ways is to connect the CO pin of the existing 4026 to the clock pin of the new 4026 (2nd digit), by using single digit seven-segment displays.
I hope the explanation will be useful.If not please reply the actual project idea so that I can provide a better solution.

 

BC56-12 seven-segment display are three common cathode displays with segment anodes wired together. These are used in a multiplexed situation where the segments are driven and the cathodes (pins 12, 8, 9) are pulled to ground one at a time.

CD4026 is a combined counter/decoder/driver chip intended for a single seven-segment display. You cannot use this in this situation.
You need a separate decoder/driver chip such as CD4511. You will have to do the counting and multiplexing in software.

Or you can go with a hardware solution and use three CD4026 and three individual common cathode seven-segment LEDs.

 

BC56-12 seven-segment display are three common cathode displays with segment anodes wired together. These are used in a multiplexed situation where the segments are driven and the cathodes (pins 12, 8, 9) are pulled to ground one at a time.

CD4026 is a combined counter/decoder/driver chip intended for a single seven-segment display. You cannot use this in this situation.
You need a separate decoder/driver chip such as CD4511. You will have to do the counting and multiplexing in software.

Or you can go with a hardware solution and use three CD4026 and three individual common cathode seven-segment LEDs.

 

Thank you
Mark