at94k40al ATMEL Corporation, at94k40al Datasheet - Page 123

• Manufacturer Part Number: at94k40al
• Description: At94kal Series Field Programmable System Level Integrated Circuit
• Manufacturer: ATMEL Corporation

4.28.7.3
1138I–FPSLI–1/08
muls16x16_32
Description
Usage
Statistics
Note:
Signed multiply of two 16-bit numbers with a 32-bit result.
R19:R18:R17:R16 = R23:R22 • R21:R20
Cycles: 19 + ret
Words: 15 + ret
Register usage: R0 to R2 and R16 to R23 (11 registers)
muls16x16_32:
clr
muls
movw
mul
movw
mulsu r23, r20
sbc
add
adc
adc
mulsu r21, r22
sbc
add
adc
adc
ret
1. The routine is non-destructive to the operands.
r2
r23, r21
r19:r18, r1:r0
r22, r20
r17:r16, r1:r0
r19, r2
r17, r0
r18, r1
r19, r2
r19, r2
r17, r0
r18, r1
r19, r2
; (signed)ah * (signed)bh
; al * bl
; (signed)ah * bl
; Sign extend
; (signed)bh * al
; Sign Extend
AT94KAL Series FPSLIC
(1)
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