I need to send RTC data to Seven segment display

[PA3040]

Dear all
I need to send RTC data to Seven segment display

RTC data : SEC , MINIS , HOURS , DAY , MONTH , YEAR

I am using 74LS248 IC for BCD to drive seven segment
I am using 4094 IC for mux

I need use single port for both BCD driver and MUX driver ( see image for wiring diagram)

MSB for BCD driver
LSB for MUX driver

can I have algorithm for above program
My MCU is 16f877a + Assembly language

 

[Pretest]

The inputs LT and RBI should be held high and the refresh rate must be at least 120Hz since you have 4 display. Wouldn't it be easier to program it in C?

 

[PA3040]

Dear Pretest,

Can you explain it more please

Thanks in advance

 

[Pretest]

LT and RBI must be held high to be able to output 0 to 9.

About the refresh rate, since you have 6 independent display the refresh frequency of each display must be at least 30Hz. If you go lower than 30Hz you will see flickering.

 

[PA3040]

Dear Pretest,
Thank you very much for reply
I need algorithm for above program, I mean while using same port for BCD data and shift register as per my picture

please advice

 

[Pretest]

Here something that could possibly do what you want. I give you pseudo code only.

Read RTC and put the result in a variable.

Select the right display by sending a 0 to your display.
Isolate the value you want to send. Put it on PD0-PD4. Toggle high then low the STB pin of the Mux to latch the enable of your display.

Repeat for each value you need to send.

Hope this helps