Hello,
I am using cc430f5137 with CCS4.Can I know how to change the two 16bit number multiplication function to multiply a fractional number (negative or positive for example 0.00378304197175636 or -0.0123878480564485) with 16 bit integer.
The two 16bit number multiplication function used is
6825.5658.mul16.txt
//*****************************************************************************
// THIS PROGRAM IS PROVIDED "AS IS". TI MAKES NO WARRANTIES OR
// REPRESENTATIONS, EITHER EXPRESS, IMPLIED OR STATUTORY,
// INCLUDING ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE, LACK OF VIRUSES, ACCURACY OR
// COMPLETENESS OF RESPONSES, RESULTS AND LACK OF NEGLIGENCE.
// TI DISCLAIMS ANY WARRANTY OF TITLE, QUIET ENJOYMENT, QUIET
// POSSESSION, AND NON-INFRINGEMENT OF ANY THIRD PARTY
// INTELLECTUAL PROPERTY RIGHTS WITH REGARD TO THE PROGRAM OR
// YOUR USE OF THE PROGRAM.
//
// IN NO EVENT SHALL TI BE LIABLE FOR ANY SPECIAL, INCIDENTAL,
// CONSEQUENTIAL OR INDIRECT DAMAGES, HOWEVER CAUSED, ON ANY
// THEORY OF LIABILITY AND WHETHER OR NOT TI HAS BEEN ADVISED
// OF THE POSSIBILITY OF SUCH DAMAGES, ARISING IN ANY WAY OUT
// OF THIS AGREEMENT, THE PROGRAM, OR YOUR USE OF THE PROGRAM.
// EXCLUDED DAMAGES INCLUDE, BUT ARE NOT LIMITED TO, COST OF
// REMOVAL OR REINSTALLATION, COMPUTER TIME, LABOR COSTS, LOSS
// OF GOODWILL, LOSS OF PROFITS, LOSS OF SAVINGS, OR LOSS OF
// USE OR INTERRUPTION OF BUSINESS. IN NO EVENT WILL TI'S
// AGGREGATE LIABILITY UNDER THIS AGREEMENT OR ARISING OUT OF
// YOUR USE OF THE PROGRAM EXCEED FIVE HUNDRED DOLLARS
// (U.S.$500).
//
// Unless otherwise stated, the Program written and copyrighted
// by Texas Instruments is distributed as "freeware". You may,
// only under TI's copyright in the Program, use and modify the
// Program without any charge or restriction. You may
// distribute to third parties, provided that you transfer a
// copy of this license to the third party and the third party
// agrees to these terms by its first use of the Program. You
// must reproduce the copyright notice and any other legend of
// ownership on each copy or partial copy, of the Program.
//
// You acknowledge and agree that the Program contains
// copyrighted material, trade secrets and other TI proprietary
// information and is protected by copyright laws,
// international copyright treaties, and trade secret laws, as
// well as other intellectual property laws. To protect TI's
// rights in the Program, you agree not to decompile, reverse
// engineer, disassemble or otherwise translate any object code
// versions of the Program to a human-readable form. You agree
// that in no event will you alter, remove or destroy any
// copyright notice included in the Program. TI reserves all
// rights not specifically granted under this license. Except
// as specifically provided herein, nothing in this agreement
// shall be construed as conferring by implication, estoppel,
// or otherwise, upon you, any license or other right under any
// TI patents, copyrights or trade secrets.
//
// You may not use the Program in non-TI devices.
//*****************************************************************************
//16x16=>32 multiply
//int32_t mul16(register int16_t x, register int16_t y)
// Use with IAR versions >= 4.0
public mul16
RSEG CODE
mul16
#define x1 r9
#define z0 r14
#define z1 r15
#define x r12
#define y r13
push r9
clr z0
mov z0,z1
mov z0,x1
tst x
jge xbooth_2
mov #-1,x1
jmp xbooth_2
xbooth_6
add x,z1
addc x1,z0
xbooth_1
rla x
rlc x1
xbooth_2
rra y
jc xbooth_5
jne xbooth_1
jmp xbooth_4
xbooth_5
sub x,z1
subc x1,z0
xbooth_3
rla x
rlc x1
rra y
jnc xbooth_6
cmp #0FFFFh,y
jne xbooth_3
xbooth_4
mov z1,r12
mov z0,r13
pop r9
ret
end
#include <msp430.h>
long mul16(register int x, register int y);
long result;
int main(void)
{
int x=1;
int y=1;
result=mul16(x,y);
__bis_SR_register(LPM0_bits); // Enter LPM4
__no_operation();
}
Thanks.
