AT94K05AL ATMEL Corporation, AT94K05AL Datasheet - Page 117

• Manufacturer Part Number: AT94K05AL
• Description: Fpslic Devices Combine 5K Gates of Atmel's Patented AT40K Fpga Architecture, a 20 Mips Avr 8-bit Risc Microprocessor Core, Numerous Fixed Microcontroller Peripheries And up to 36K Bytes of Program And Data SRAM.
• Manufacturer: ATMEL Corporation

fmuls16x16_32
fmac16x16_32
Rev. 1138F–FPSLI–06/02
Description
Usage
Statistics
Note:
Description
Usage
Statistics
Signed fractional multiply of two 16-bit numbers with a 32-bit result.
R19:R18:R17:R16 = (R23:R22 • R21:R20) << 1
Cycles: 20 + ret
Words: 16 + ret
Register usage: R0 to R2 and R16 to R23 (11 registers)
fmuls16x16_32:
Signed fractional multiply-accumulate of two 16-bit numbers with a 32-bit result.
R19:R18:R17:R16 += (R23:R22 • R21:R20) << 1
Cycles: 25 + ret
Words: 21 + ret
Register usage: R0 to R2 and R16 to R23 (11 registers)
fmac16x16_32:
clr
fmuls r23, r21
movw
fmul
adc
movw
fmulsu
sbc
add
adc
adc
fmulsu
sbc
add
adc
adc
ret
clr
fmuls r23, r21
add
adc
fmul
adc
adc
add
1. The routine is non-destructive to the operands.
r2
r19:r18, r1:r0
r22, r20
r18, r2
r17:r16, r1:r0
r19, r2
r17, r0
r18, r1
r19, r2
r19, r2
r17, r0
r18, r1
r19, r2
r2
r18, r0
r19, r1
r22, r20
r18, r2
r19, r2
r16, r0
r23, r20
r21, r22
; ( (signed)ah * (signed)bh ) << 1
; ( al * bl ) << 1
; ( (signed)ah * bl ) << 1
; Sign extend
; ( (signed)bh * al ) << 1
; Sign extend
; Register usage optimized
; ( (signed)ah * (signed)bh ) << 1
; ( al * bl ) << 1
AT94K Series FPSLIC
(1)
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