10-keybord device for BCD Encoder using Multisim.

[tourmansasurai]

I'm using Multisim (Ver10.1.1). I want to find a way to make a BCD encoder which input is done by an ten-keys like a calculator.I've found a 'NUMERIC_KEYPAD_4x4" in KEWPADS family under MASDTER DATABASE.So, I'm planning to use this KEYPAD and push the 0-9 keys for getting BCD output of binary 4-bits data. 

I'll appreciate any information that will be useful for that purpose.

[Andrew.J]

Hi

DF below telling HOW to use Keypad.

The example is good.

http://forums.ni.com/ni/board/message?board.id=370&message.id=6959&query.id=6833775#M6959

[tourmansasurai]

Thank you Andrew for your response.

The MCU example seems to be a modern solution for simulating a calculator.
However, I'd like to use only a conventional TTL or CMOS logic-ICs for simulating a calculator using a KEYPAD. This is just for an educational purpose.

Attached file is my latest circuit which Input is done by a simple switches for decimal inputs: It can add only single figures and the maximum effective sum value is 9.
"74147" is 10-Line to 4-Line BCD Encoder that converts the decimal input to a BCD output. "74181" is an Arithmetic Logic Units.
My plan is to replace the switches & 74147s to a NUMERIC_KEYPAD & BCD encoder logic ICs or circuits for demonstrating the calculator more familiar.

I'll wait for additional information from anyone.

[faizan88]

sir can you please tell me how do i make 2 digit calculator? using encoder shift registers adders and decioder i work on 1 digit calculator but dont on 2 digit kindly let me know