PIC18F6621-I/PT Microchip Technology Inc., PIC18F6621-I/PT Datasheet - Page 315

• Manufacturer Part Number: PIC18F6621-I/PT
• Description: 64 PIN, 64 KB FLASH, 3840 RAM, 52 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F6621-I/PT

• A/d Inputs: 12-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 10 MIPS
• Eeprom Memory: 1024 Bytes
• Input Output: 54
• Interface: I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 64-pin TQFP
• Programmable Memory: 64K Bytes
• Ram Size: 3.8K Bytes
• Speed: 40 MHz
• Timers: 2-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

TBLRD
Syntax:
Operands:
Operation:
Status Affected: None
Encoding:
Description:
Words:
Cycles:
 2005 Microchip Technology Inc.
Q Cycle Activity:
operation
Decode
No
Q1
(Read Program
[ label ]
None
(Prog Mem (TBLPTR)) → TABLAT;
TBLPTR – No Change
if TBLRD*+
(Prog Mem (TBLPTR)) → TABLAT;
(TBLPTR) + 1 → TBLPTR
if TBLRD*-
(Prog Mem (TBLPTR)) → TABLAT;
(TBLPTR) – 1 → TBLPTR
if TBLRD+*
(TBLPTR) + 1 → TBLPTR;
(Prog Mem (TBLPTR)) → TABLAT
This instruction is used to read the contents
of Program Memory (P.M.). To address the
program memory, a pointer called Table
Pointer (TBLPTR) is used.
The TBLPTR (a 21-bit pointer) points to
each byte in the program memory. TBLPTR
has a 2-Mbyte address range.
The TBLRD instruction can modify the value
of TBLPTR as follows:
• no change
• post-increment
• post-decrement
• pre-increment
1
2
Table Read
if TBLRD*
No operation
TBLPTR[0] = 0: Least Significant Byte of
TBLPTR[0] = 1: Most Significant Byte of
operation
Memory)
0000
No
Q2
TBLRD ( *; *+; *-; +*)
0000
operation
operation
Program Memory Word
Program Memory Word
No
No
Q3
0000
No operation
operation
TABLAT)
PIC18F6525/6621/8525/8621
(Write
No
nn=0 *
Q4
10nn
=1 *+
=2 *-
=3 +*
TBLRD
Example 1:
Example 2:
Before Instruction
After Instruction
Before Instruction
After Instruction
TABLAT
TBLPTR
MEMORY(0x00A356)
TABLAT
TBLPTR
TABLAT
TBLPTR
MEMORY(0x01A357)
MEMORY(0x01A358)
TABLAT
TBLPTR
Table Read (Continued)
TBLRD
TBLRD
*+ ;
+* ;
=
=
=
=
=
=
=
=
=
=
=
DS39612B-page 313
0x55
0x00A356
0x34
0x34
0x00A357
0xAA
0x01A357
0x12
0x34
0x34
0x01A358