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[英]Where can I find information about programming the TI TMS320C64xx DMA controller
[英]What exactl hex information is telling me to send? Where LC and xx yy zz is not clear to me
目前尚不清楚,我必须按命令发送什么? 这是否意味着我必须分两步发送? (它连接到PC的USB硬件,我可以发送命令以获取信息)
1)第一个必须为00 A4 08 0c 04 df 01 40 31 {LC?? what does it mean}
00 A4 08 0c 04 df 01 40 31 {LC?? what does it mean}
?
2)第二个必须为00 b0 xx yy zz
{什么是xx且yy和zz必须为??}
参考说如下:
To select those files, you have to use:
00 A4 08 0c 04 df 01 40 xx Lc
00 : ISO CLAss (~standard ISO)
A4 : ISO file_select INStruction
08 0c : P1 P2 for this operation (otherwise you get an error...)
04 : length of the 'path'
df 01 : directory for Id data
40 xx : the files id
31 : owner's identity (names, birth,...)
33 : owner's address
35 : owner's picture
Lc is the expected answer length (?)
Once the file is successfully selected (SW1:SW2 == 90:00),
one can 'binary_read' the content with
00 b0 xx yy zz
00 : ISO CLAss (~standard ISO APDU)
b0 : ISO read_binary INStruction
xx yy : offset in the file (256*xx)+yy
zz : number of bytes to read
规范中的注释清楚地回答了您的问题。
Lc
是预期的响应长度。
在“ binary_read”中, xx
和yy
分别是文件偏移量的16位值的MSB和LSB,而zz
是要读取的块的字节长度。
如果要对偏移量n进行赋值,则:
xx = n / 256 ;
yy = n % 256 ;
或者:
xx = (n >> 8) & 0xff ;
yy = n & 0xff ;
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