DM164120-1 Microchip Technology, DM164120-1 Datasheet - Page 21

• 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.
3.2.3
Building on Lessons 1 and 2, which showed how to light up a LED and then make it
blink with a delay loop, this lesson adds rotation. It will light up DS4 and then shift it to
DS3, then DS2, then DS1 and back to DS4.
New Instructions
Rotate Program Flow
• First, initialize the I/O port and the Display,
• Copy the Display variable to the I/O Port, then
• Delay for a little while
• Rotate the display
FIGURE 3-1:
Note:
MOVLW
MOVWF
MOVF
RRF
RLF
Lesson 3: Rotate (Move the LED)
Moving a file register to itself looks like a NOP at first. However, it has a
useful side effect in that the Z flag is set to reflect the value. In other words,
MOVF fileregister,f is a convenient way to test whether or not the
value is zero without affecting the contents of the Wreg.
ROTATE PROGRAM FLOW
Loads Wreg with a literal value
Moves the contents of Wreg to a file register
Moves the contents of a file register, either to Wreg or back
into the file register (see note)
Rotate file register right
Rotate file register left
Initialize I/O Port
Did it overflow?
Put Up Display
Rotate Display
Reset Display
LPC Demo Board Lessons
Delay
No
Yes
DS51556A-page 17