DM164120-1 Microchip Technology, DM164120-1 Datasheet - Page 29

• Manufacturer Part Number: DM164120-1
• Description: BOARD DEMO PICKIT 2 LP COUNT
• Manufacturer: Microchip Technology
• Type: MCUr

Specifications of DM164120-1

• Contents: 3 Boards (1 Populated, 2 Bare)
• Processor To Be Evaluated: PIC16F690
• Silicon Manufacturer: Microchip
• Core Architecture: PIC
• Core Sub-architecture: PIC16
• Silicon Core Number: PIC16F
• Silicon Family Name: PIC16F6xxx
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: 28-pin PIC16C, 16F, 18C, 18F
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

© 2005 Microchip Technology Inc.
3.2.7
Lesson 7 combines Lessons 5 and 6 using the button to reverse the direction of rotation
when the button is pressed and adjusting the potentiometer to control the speed of
rotation.
The program needs to keep track of rotation direction and new code needs to be added
to rotate in the other direction.
Lesson 5 rotates right and checks for a ‘1’ in the Carry bit to determine when to restart
the sequence. In Lesson 7, we’ll also need to rotate left and check for a ‘1’ in bit 4 of
the display. When the ‘1’ shows up in bit 4 of the display, re-insert it into the bit 0
position.
EXAMPLE 3-6:
Original Version:
Rotate
Bidirectional Version:
Rotate
RotateRight
RotateLeft
RRF
BTFSC STATUS,C
BSF
BCF
BTFSS Direction,0
GOTO
RRF
BTFSC STATUS,C
BSF
GOTO
RLF
BTFSC Display,4
BSF
GOTO
Lesson 7: Reversible Variable Speed Rotate
Display,f
Display,3
STATUS,C
RotateLeft
Display,f
Display,3
MainLoop
Display,f
Display,0
MainLoop
REVERSIBLE VARIABLE SPEED ROTATE EXAMPLE
;Did the bit rotate into the carry?
;yes, put it into bit 3.
;ensure the carry bit is clear
;Did the bit rotate into the carry?
;yes, put it into bit 3.
;did it rotate out of the display
;yes, put it into bit 0
LPC Demo Board Lessons
DS51556A-page 25