• slider image 442
  • slider image 483
  • slider image 484
  • slider image 485
  • slider image 486
  • slider image 487
:::


Browsing this Thread:   1 Anonymous Users






一个问题
#1
新會員
新會員


查看用戶資訊
想问个KEELOQ解码程序的问题:
byte aux;

void Decrypt()
{
byte i, j, key;
sbyte p;

p = 1;

for (j=66; j>0; j--)
{
key = DKEY[p--];
if (p<0)
p+=8;

for (i=8; i>0; i--)
{
// NLF
if ( BIT_TEST( Buffer[3],6))
{
if ( !BIT_TEST( Buffer[3],1))
aux = 0b00111010; // 10
else
aux = 0b01011100; // 11
}
else
{
if ( !BIT_TEST( Buffer[3],1))
aux = 0b01110100; // 00
else
aux = 0b00101110; // 01
}


// move bit in position 7
if ( BIT_TEST( Buffer[2],3))
#asm
swapf aux,f
#endasm
if ( BIT_TEST( Buffer[1],0))
aux<<=2;
if (BIT_TEST( Buffer[0],0))
aux<<=1;

// xor with Buffer and Dkey
aux ^= Buffer[1] ^ Buffer[3] ^ key;

// shift in buffer
shift_left( Buffer, 4, BIT_TEST( aux,7));

key<<=1;
} // for i

} // for j

我想问一下:程序中的“swapf aux,f”是什么 意思?
是交换的意思吗?那其中的f寄存器中的值是多少呢?谢谢!!

發表於: 2009/1/9 11:46
Twitter Facebook Google Plus Linkedin Del.icio.us Digg Reddit Mr. Wong 頂部


Re: 一个问题
#2
高級會員
高級會員


查看用戶資訊
swapf aux,f
aux if=#h'a5'
swapf後aux=#h'5a'

發表於: 2009/1/9 14:41
Twitter Facebook Google Plus Linkedin Del.icio.us Digg Reddit Mr. Wong 頂部







You can view topic.
不可以 發起新主題
You cannot reply to posts.
You cannot edit your posts.
You cannot delete your posts.
You cannot add new polls.
You cannot vote in polls.
You cannot attach files to posts.
You cannot post without approval.
You cannot use topic type.
You cannot use HTML syntax.
You cannot use signature.
You cannot create PDF files.
You cannot get print page.

[進階搜尋]


:::

Microchip連結

https://www.facebook.com/microchiptechnologytaiwan/
http://www.microchip.com.tw/modules/tad_uploader/index.php?of_cat_sn=13
https://mu.microchip.com/page/tmu
http://elearning.microchip.com.tw/modules/tad_link/index.php?cate_sn=1
https://page.microchip.com/APAC-PrefCenters-TW.html
http://www.microchip.com/
http://www.microchip.com/treelink
http://www.microchipdirect.com/
http://www.microchip.com.cn/newcommunity/index.php?m=Video&a=index&id=103
http://www.microchip.com.tw/modules/tad_uploader/index.php?of_cat_sn=2
http://www.microchip.com.tw/Data_CD/eLearning/index.html
http://www.microchip.com.tw/RTC/RTC_DVD/
https://www.microchip.com/development-tools/
https://www.youtube.com/user/MicrochipTechnology
[ more... ]

教育訓練中心

!開發工具購買
辦法說明 [業界客戶] [教育單位]
----------------------------------
!校園樣品申請
辦法說明 [教師資格] [學生資格]
----------------------------------