Assignment 3 -- This assignment relates to the 18F85K22 PIC chip. (microcontroller)

1. For the following section of program code, fill the actual Ram address that is loaded with W. Fill in the full 12-bit value if the Banks are selected. The a field selects how Ram is accessed.

a. MOVLB 0x0

MOVWF PCL,0 Bank address-_________ f address-______________

b. MOVLB 0x5

MOVWF STATUS,1 Bank address-_________ f address-______________

c. MOVLB 0x3

MOVWF 0xFEE,0 Bank address-_________ f address-______________

d MOVLB 0xF

MOVWF 0xFEE,1 Bank address-_________ f address-______________

2. What are the power-on reset values for the following SFR registers?

TRISC ________________________

PORTD ________________________

SSPCON1 ________________________

IPR1 ________________________

3. Explain what happens in the microcontroller when the following instructions are executed;

RETURN

RETFIE -

CALL SUB2-

GOTO NEXT-

4. What are the addresses of the following SFR (special function registers)? Full 12-bit values.

RCON _____________

TXREG _____________

EEADR _____________

PRODL _____________

5. For the following section of a program answer the questions. Explain clearly.

LongDelay

movlw .255

movwf DelayT2,0

ldelaya

call Delay

decfsz DelayT2,f,0

goto ldelaya

return

Delay

movlw .255

movwf DelayTemp,0

delaya

decfsz DelayTemp,f ,0

goto delaya

return

a. What does this program do? Explain its operation.

b. What labels need to be defined?

c. Can I slow down this subroutine without major changes?

d. Can I speed up this subroutine without major changes?

6. Convert the following instructions to values instead of labels.

BTFSS STATUS, DC

BTFSS ________, _____

BCF INTCON, INTF

BCF ________, _____

7. Fill in the table for the different types of memory in the 18F85K22 PIC chip.

Type Main Use(s) Memory size bit length

8. Given the following section of code,

ORG .250

LINE1 MOVLW 25

MOVWF TEST,1

-What is the address of the instruction at LINE1?- ______________________