FY-3-b Easy 8085 Program To Unpack The BCD Number And Store The Two Digits In Memory Locations

Table of Contents

8085 program to Unpack the BCD number and store the two digits in memory locations

Two digit BCD number is stored in memory location 4200H. Unpack the BCD
number and store the two digits in memory locations 4300H and 4301H such that
memory location 4300H will have lower BCD digit.

Note : For following example we have changed addresses.

0700 91

LDA 0700     #A = 91 || 0701 = 00 || 0702 = 00
ANI 0F           #A = 01 || 0701 = 00 || 0702 = 00
STA 0701      #A = 01 || 0701 = 01 || 0702 = 00
LDA 0700     #A = 91 || 0701 = 01 || 0702 = 00
ANI F0           #A = 90 || 0701 = 01 || 0702 = 00
RRC                #A = 48
RRC                #A = 24
RRC                #A = 12
RRC                 #A = 09 
STA 0702        #A = 09|| 0701 = 01 || 0702 = 09
HLT

LDA 0700 – A 24 bits (3 bytes) command which will load content of memory location 0700 in register A i.e. Accumulator.

ANI 0F – It stands for “AND Immediate with Accumulator”. It will perform AND operation of operand with content of Accumulator. In this case 91 AND 0F.

STA 0701 – A 24 bits command which will store data of accumulator in memory location 0701.

ANI F0 – It stands for “AND Immediate with Accumulator”. It will perform AND operation of operand with content of Accumulator. In this case 91 AND F0.

RRC – It stands for “Rotate Right Accumulator”. it will rotate the Accumulator current content to the right by 1-bit position. LSB bit will be shifted in MSB and Carry Flag.

STA 0702 – A 24 bits command which will store data of accumulator in memory location 0702.

HTL – It means Halt the microprocessor.