Atmel SAM4S Xplained Pro Starter Kit Atmel ATSAM4S-XSTK ATSAM4S-XSTK Data Sheet

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SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

Unsigned Add 16 and Unsigned Add 8

Syntax

op{cond}{Rd,} Rn, Rm

where:

op

is any of:

UADD16 Performs two 16-bit unsigned integer additions.

UADD8 Performs four 8-bit unsigned integer additions.

cond

Rd

is the destination register.

Rn

is the first register holding the operand.

Rm

is the second register holding the operand.

Operation

Use these instructions to add 16- and 8-bit unsigned data:

The UADD16 instruction:

1.

Adds each halfword from the first operand to the corresponding halfword of the second operand.

2.

Writes the unsigned result in the corresponding halfwords of the destination register.

The UADD16 instruction:

1.

Adds each byte of the first operand to the corresponding byte of the second operand.

2.

Writes the unsigned result in the corresponding byte of the destination register.

Restrictions

Do not use SP and do not use PC

Condition Flags

These instructions do not change the flags.

Examples

UADD16 R1, R0      ; Adds halfwords in R0 to corresponding halfword of R1, 

                   ; writes to corresponding halfword of R1

UADD8  R4, R0, R5  ; Adds bytes of R0 to corresponding byte in R5 and 

                   ; writes to corresponding byte in R4.