The document describes a program example using stack and subroutines. The main program initializes the stack pointer to 1000H and loads the H register with 2F37H. It then calls a subroutine at 3000H which pushes the H register onto the stack, performs an addition, and returns. After returning from the subroutine, the program halts. When it halts, the registers would contain: PC = 2103H, SP = 1000H, B = 2F38H, C = 38H, H = 2F38H, L = 38H.

1. MICROPROCESSOR 8085
LECTURE 17
PROGRAMMING EXAMPLE-VIII
STACK & SUBROUTINE
PROF. SANDIP DAS

2. Memory address Mnemonics, operands
2000 LXI SP, 1000 H
2003 LXI H, 2F37 H
2006 XRA A
2007 MOV A, H
2008 INX H
2009 PUSH H
200A CZ, 20FF H
200B JMP 3000
200E HLT
3000 HLT
20FF ADD H
2100 RZ
2101 POP B
2102 RNZ
2103 HLT
Determine the contents of the registers: PC, SP, B, C, H, L after a HALT instruction
executed
38
STAC
K
2F
2003
2007
2006
2008
200A
200B
MAIN
PROGRAM
20FF
2101
2100
2102
2103
SUBROUTI
NE
200E
2009
100
0
B
2F
C
38
H
2F
L
37
2F 37
2F 38
A
SP
00
2F
SP0FF
F
SP0FF
E
ZF
1
5E