DM164120-2 Microchip Technology, DM164120-2 Datasheet - Page 15

• 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

2.4
© 2007 Microchip Technology Inc.
ASSEMBLER BASICS
Mid-Range PIC
Numbers in the Assembler
Unless otherwise specified, the assembler assumes any numeric constants in the
program are hexadecimal (base 16). Binary (base 2), Octal (base 8), Decimal (base
10), and ASCII coding are also supported.
Org (Origin)
End
Defining Data Memory Locations
EXAMPLE 2-1:
Note that if used as a literal, the label names will take on the value assigned. If used as
an address operand in an instruction, the label names point to the contents of the file
register with the address of the label’s value.
Unless there is a reason to name a specific location address, the cblock/endc
method is preferred. The advantage is that as variables come and go through the
development process, the cblock keeps the block to a minimum. Using one of the
other methods, you may have to go back and find an unused location.
#define Length
Length
Length
Width
Area:2
Girth
Org tells the Assembler an address at which to start generating code. Normally
we start coding at the Reset vector address ‘0000’, but it could be anywhere.
Baseline devices have a Reset vector at the last location in program memory, so
it’s good practice to have a GOTO instruction pointing to the beginning of the
program.
End tells the assembler to stop assembling. There must be one at the end of the
program. It does not necessarily have to be at the end of the file, but nothing after
the end statement will be assembled.
There are three ways to name a location (see Example 2-1). All are equivalent in
that the location name label will be substituted with the value assigned to it during
assembly.
Hexadecimal
Decima
Octal
Binary
ASCII
cblock
endc
l
equ
®
Microcontroller Architectural Overview
DEFINING DATA MEMORY
12 or 0x12 or H'12
.12 or D'12'
O'12'
B'00010010'
A'c' or 'c'
0x20
0x20
0x20
;c-like syntax
;equate 0x20 with the symbol
;start a block of variables
;this will be at address 0x20
;this will be at address 0x21
;this is 2 bytes long, starting at
;address 0x22
;this will be at address 0x24
'
DS41296B-page 11