Microchip Technology MA160014 Hoja De Datos

 2010-2012 Microchip Technology Inc.

DS41412F-page 383

         

         

Syntax:

BNC    n

Operands:

-128 

 n  127

Operation:

if CARRY bit is ‘0’
(PC) + 2 + 2n 

 PC

Status Affected:

None

Encoding:

1110

0011

nnnn

nnnn

Description:

If the CARRY bit is ‘0’, then the program 
will branch.
The 2’s complement number ‘2n’ is 
added to the PC. Since the PC will have 
incremented to fetch the next 
instruction, the new address will be 
PC + 2 + 2n. This instruction is then a 
two-cycle instruction.

Words:

1

Cycles:

1(2)

Q Cycle Activity:
If Jump:

Q1

Q2

Q3

Q4

Decode

Read literal 

‘n’

Process 

Data

Write to PC

No 

operation

No 

operation

No 

operation

No 

operation

If No Jump:

Q1

Q2

Q3

Q4

Decode

Read literal 

‘n’

Process 

Data

No 

operation

Example:

HERE

BNC

Jump

Before Instruction

PC

=

address (HERE)

After Instruction

If CARRY

= 

0;

PC

= address 

(Jump)

If CARRY

= 

1;

PC

= address (HERE + 2)

Syntax:

BNN    n

Operands:

-128 

 n  127

Operation:

if NEGATIVE bit is ‘0’
(PC) + 2 + 2n 

 PC

Status Affected:

None

Encoding:

1110

0111

nnnn

nnnn

Description:

If the NEGATIVE bit is ‘0’, then the 
program will branch.
The 2’s complement number ‘2n’ is 
added to the PC. Since the PC will have 
incremented to fetch the next 
instruction, the new address will be 
PC + 2 + 2n. This instruction is then a 
two-cycle instruction.

Words:

1

Cycles:

1(2)

Q Cycle Activity:
If Jump:

Q1

Q2

Q3

Q4

Decode

Read literal 

‘n’

Process 

Data

Write to PC

No 

operation

No 

operation

No 

operation

No 

operation

If No Jump:

Q1

Q2

Q3

Q4

Decode

Read literal 

‘n’

Process 

Data

No 

operation

Example:

HERE

BNN

Jump

Before Instruction

PC

=

address (HERE)

After Instruction

If NEGATIVE

= 

0;

PC

= address (Jump)

If NEGATIVE

= 

1;

PC

= address (HERE + 2)