$1)$ While it is true that an instruction with direct addressing can only access data numbers at

addresses in the range from $0000$ to $00$FF$,$ is it true that the instruction must also be within this

address range?

$2)$ Is the offset in an instruction with indexed addressing interpreted as an unsigned number or a

$($signed$)$ two$$s complement number?

$3)$ What is the addressing mode of an instruction that contains a constant data number within the

instruction code?

$4)$ When a double$-$byte data number is stored in memory, is the high byte placed at the higher or

lower of the two addresses?

$5)$ What single instruction will set, without affecting any other condition code bits, the C bit? The

N bit?

ECET $2570$ Spring $2024$

Homework $042$ of $2$

$6)$ What is the machine code for a single instruction that undoubtedly puts zero in the B

accumulator $($two answers!$),$ and another instruction that puts zero into memory location

C$221?$

$7)$ Write a program module to exchange the numbers in the A and B accumulators.

$8)$ Consider a BRA opcode at location $$30$E$5.$

a$.$ Where will the MPU go if the offset is $$57?$

b$.$ Where will the MPU go if the offset is $$83?$

c$.$ What offset is required to branch to location $$3100?$

d$.$ What offset is required to branch to location $$30$B$3?$

e$.$ What range of addresses could be branched to from $$30$E$5?$