help:How to change the attribute of the serial port in embedded linux?
When I tried to change the attibute of the serial port in embedded linux
with the function tcgetattr() and tcsetattr(), I found that they didn't work,
although the return of these two functions were both '0', i.e. success.
Another problem. In the linux on PC, I can read all the message in the
buffer of serial port with the function read() only once, and it returns the
number of the characters in the buffer. But when I read the message in embedded
linux, it always stops when it encounters <enter> or <space>, and I can just
get part of the message, and don't know exactly the number of characters in the
buffer.
For example, suppose the string in the buffer is
"abcd<enter>efgh<space>ijk". When on PC , after using the function read(), I
can get the whole string and the number 13 (11 letters and a <enter> and a
<space>). But in embedded linux, I can only get the string "abcd" and the
number 4 with one read(). Read() again, I can get "efgh" and the number 4.
Again and again, I can get "ijk" and number 3. Again and again and again, I
will get "abcd" and number 4 again. Then it repeats.
What I want is that the serial port in embedded linux can perform as the
one in the linux on PC, i.e., I can read all the message and get the exact
number with one read().
Can you tell me how to do?
I use PXA250, linux kernel 2.4.18,patch-2.4.18-rmk6 patches by Russell King
and diff-2.4.18-rmk6-pxa2 by Nicolas Pitre
Regards,
==================================
Zheng Hao
hallosky@xxxxxxxxxxx
2003-12-02
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