DM164120-2 Microchip Technology, DM164120-2 Datasheet - Page 19

• Manufacturer Part Number: DM164120-2
• Description: BOARD DEMO PICKIT 2 44PIN
• Manufacturer: Microchip Technology
• Type: MCUr

Specifications of DM164120-2

• Contents: 3 Boards (1 Populated, 2 Bare)
• Processor To Be Evaluated: PIC16F
• Silicon Manufacturer: Microchip
• Kit Contents: PIC16F Device, 2 PCB Boards
• Features: Small Surface Mount Prototype Area, Two Bare PCB Boards
• Development Tool Type: Hardware - Daughter Card
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PIC16F887
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

© 2007 Microchip Technology Inc.
For more information, refer to the I/O Ports section of the PIC16F882/883/884/886/887
Data Sheet (DS41291).
3.2.2
The first lesson showed how to turn on a LED, this lesson shows how to make it blink.
While this might seem a trivial change from Lesson 1, it gives a context to explore
several more instructions.
New Instructions
EXAMPLE 3-2:
While adding a BCF instruction and making it loop will make it blink. It will blink so fast
you won’t see it, it will only look dim. That loop requires 4 instruction times to execute.
The first instruction turns it on. The second one turns it off. The GOTO takes two instruc-
tion times, which means it will be on for 25% of the time.
As configured, the PIC
this rate, the blinking needs to be slowed down so that the blinking can be seen, which
can be done by using a delay loop.
Note:
CLRF
INCF
DECF
INCFSZ
DECFSZ
GOTO
Loop
BSF
BCF
GOTO
Blink (Delay Loop)
Counting cycles – Relating clock speed to instruction speed. The processor
requires 4 clocks to execute an instruction. Since the internal oscillator as
used in these lessons runs at 4 MHz, the instruction rate is 1 MHz.
PORTD,0
PORTD,0
Loop
Clear file register
Increment file register
Decrement file register
Increment file register, Skip next instruction if zero
Decrement file register, Skip next instruction if zero
Jump to a new location in the program
PICKIT 2, LESSON 2: BLINK
®
microcontroller executes 1 million instructions per second. At
44-Pin Demo Board Lessons
;turn on LED D0
;turn off LED D0
;do it again
DS41296B-page 15