PIC18F4539-ESLASHMLSQTP datasheet(252/322 Pages) MICROCHIP

252 / 322 page

PIC18FXX39

DS30485A-page 250

Preliminary

 2002 Microchip Technology Inc.

TBLWT

Table Write

Syntax:

[ label ]

TBLWT ( *; *+; *-; +*)

Operands:

None

Operation:

if TBLWT*,

(TABLAT)

→ Holding Register;

TBLPTR - No Change;

if TBLWT*+,

(TABLAT)

→ Holding Register;

(TBLPTR) +1

→ TBLPTR;

if TBLWT*-,

(TABLAT)

→ Holding Register;

(TBLPTR) -1

→ TBLPTR;

if TBLWT+*,

(TBLPTR) +1

→ TBLPTR;

(TABLAT)

→ Holding Register;

Status Affected: None

Encoding:

0000

11nn

nn=0 *

=1 *+

=2 *-

=3 +*

Description:

This instruction uses the 3 LSbs of the

TBLPTR to determine which of the 8

holding registers the TABLAT data is

written to. The 8 holding registers are

used to program the contents of Pro-

gram Memory (P.M.). See Section 5.0

for information on writing to FLASH

memory.

The TBLPTR (a 21-bit pointer) points

to each byte in the program memory.

TBLPTR has a 2 MBtye address

range. The LSb of the TBLPTR selects

which byte of the program memory

location to access.

TBLPTR[0] = 0: Least Significant

Byte of Program

Memory Word

TBLPTR[0] = 1: Most Significant

Byte of Program

Memory Word

The TBLWT instruction can modify the

value of TBLPTR as follows:

• no change

• post-increment

• post-decrement

• pre-increment

Words:

Cycles:

Q Cycle Activity:

Decode

operation

(Read

TABLAT)

operation

(Write to Holding

TBLWT

Table Write (Continued)

Example1:

TBLWT

*+;

Before Instruction

TABLAT

0x55

TBLPTR

0x00A356

HOLDING REGISTER

(0x00A356)

0xFF

After Instructions (table write completion)

TABLAT

0x55

TBLPTR

0x00A357

HOLDING REGISTER

(0x00A356)

0x55

Example 2:

TBLWT

+*;

Before Instruction

TABLAT

0x34

TBLPTR

0x01389A

HOLDING REGISTER

(0x01389A)

0xFF

HOLDING REGISTER

(0x01389B)

0xFF

After Instruction (table write completion)

TABLAT

0x34

TBLPTR

0x01389B

HOLDING REGISTER

(0x01389A)

0xFF

HOLDING REGISTER

(0x01389B)

0x34

PIC18F4539-E/MLSQTP Datasheet(PDF) 252 Page - Microchip Technology

PIC18F4539-E/MLSQTP Datasheet(HTML) 252 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL