at94k40al ATMEL Corporation, at94k40al Datasheet - Page 122

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

4.28.7.2
122
AT94KAL Series FPSLIC
mul16x16_32
Description
Usage
Statistics
Note:
Unsigned multiply of two 16-bit numbers with a 32-bit result.
R19:R18:R17:R16 = R23:R22 • R21:R20
Cycles: 17 + ret
Words: 13 + ret
Register usage: R0 to R2 and R16 to R23 (11 registers)
mul16x16_32:
clr
mul
movw
mul
movw
mul
add
adc
adc
mul
add
adc
adc
ret
1. Full orthogonality, i.e., any register pair can be used as long as the result and the two oper-
ands do not share register pairs. The routine is non-destructive to the operands.
r2
r23, r21
r19:r18, r1:r0
r22, r20
r17:r16, r1:r0
r23, r20
r17, r0
r18, r1
r19, r2
r21, r22
r17, r0
r18, r1
r19, r2
; ah * bh
; al * bl
; ah * bl
; bh * al
(1)
1138I–FPSLI–1/08