1. Exercise 1: Binary number and hex number
Decimal
Hex
0000
0001 1
0010 2
0011 3
0100 4
0101 5
0110 6
0111 7
1000 8
1001 9
1010 10 A
1011 11 B
1100 12 C
1101 13 D
1110 14 E
1111 15 F
Exercise 1: Binary number and hex number
A binary number can be 1 or 0
4 binary numbers make up a hexadecimal (hex) number (0->F)
Exercise1
Convert 3AH into binary .
Convert a binary number B into hex and decimal.

2. Exercise2 : A simple program , fill in ‘?’
After power up, first instruction is in 0000H, PC=0000H
Address
(H=Hex)
8-bit content (data)=instructions
(Hex)
PC before
Running the instruction (hex)
PC after
0BC8
Instruction k = 25: (meaning R0<=R0+1) ? …
0AC1
0AC0
Instruction j = 24 (meaning :goto 0BC8)
0001
Instruction 2=xx
0000
Instruction1=2B (meaning : goto 0AC0H)

3. Exercise 3: Program to find 2+3=?, Fill in ‘?’
PC=program counter; R0=general purpose register 0
Address
(H=Hex)
8-bit content (data)
The machine code is make up for this example
Before the instruction is run
After the instruction is run PC R0
0F00
What is the Content after the program is run?
0AD3
3F=stop ?
0AD2
C0=Save R0 into address location 0F00 and clear R0
0AD1
2E=Add 2 to Reg .R0
0AD0
15=Move 3 into Reg. R0 …
0001
0000
2B=Goto address 0AD0
0 (after reset)

4. Exercise 4: More/less significant bytes
Consider the hexadecimal (base 16) 32-bit number 12342A3F(H)=1x167+2x166+3x165+4x164+2x163+10x162+3x161+15x160
This number has four bytes 12, 34, 2A, 3F (4x8=32-bits)
Bytes/bits with higher weighting are “more significant” e.g. the byte 34 is more significant than 2A
Bytes/bits with lower weighting are “less significant”
We also use terms “most significant byte/bit” and “least significant byte/bit”
Excise4: For 12342A3F(H)
Write the binary number.
What is the most significant byte/bit?
What is the least significant byte/bit?

5. Exercise 5, fill in ‘?’ Save 0x2EAB057E in memory starting from 0x4000
Address (data in each address location must be 8-bit)
Little endian data
Big endian
data
0x4000 7E ?
0x4001
0x4002
0x4003