INSTRUCTION SET REFERENCE

Table A-6. Instruction Set (Continued)

Mnemonic

Operation

Instruction Format

TIJMP

TABLE INDIRECT JUMP. Causes execution

 

to continue at an address selected from a

 

table of addresses.

 

The first word register, TBASE, contains the

 

16-bit address of the beginning of the jump

 

table. TBASE can be located in RAM up to

 

FEH without windowing or above FFH with

 

windowing. The jump table itself can be

 

placed at any nonreserved memory location

 

on a word boundary.

 

The second word register, INDEX, contains

 

the 16-bit address that points to a register

 

containing a 7-bit value. This value is used to

 

calculate the offset into the jump table. Like

 

TBASE, INDEX can be located in RAM up to

 

FEH without windowing or above FFH with

 

windowing. Note that the 16-bit address

 

contained in INDEX is absolute; it disregards

 

any windowing that may be in effect when the

 

TIJMP instruction is executed.

 

The byte operand, #MASK, is 7-bit immediate

 

data to mask INDEX. #MASK is ANDed with

 

INDEX to determine the offset (OFFSET).

 

OFFSET is multiplied by two, then added to

 

the base address (TBASE) to determine the

 

destination address (DEST X).

 

[INDEX] AND #MASK = OFFSET

 

(2 × OFFSET) + TBASE = DEST X

 

PC (DEST X)

TIJMP TBASE, [INDEX], #MASK

(11100010) [INDEX] (#MASK) (TBASE)

NOTE: TIJMP multiplies OFFSET by two to provide for word alignment of the jump table.

PSW Flag Settings

Z

 

N

 

C

V

VT

ST

 

 

TRAP

SOFTWARE TRAP. This instruction causes

 

an interrupt call that is vectored through

 

location 2010H. The operation of this

 

instruction is not affected by the state of the

 

interrupt enable flag (I) in the PSW. Interrupt

 

calls cannot occur immediately following this

 

instruction.

 

 

 

 

 

 

 

SP SP – 2

 

 

 

 

 

 

(SP) PC

 

 

 

 

 

 

 

PC (2010H)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PSW Flag Settings

 

 

 

Z

N

C

V

VT

ST

 

 

 

— —

 

 

TRAP

(11110111)

NOTE: This instruction is not supported by assemblers. The TRAP instruction is intended for use by development tools. These tools may not support user-application of this instruction.

A-39

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Intel 8XC196MC, 8XC196MD, 8XC196MH manual Index and #MASK = Offset, × Offset + Tbase = Dest, Tijmp TBASE, INDEX, #MASK