RTOS/rtems
1
0
Fork 0
forked from Imagelibrary/rtems
Code Pull Requests Activity

2009-01-29 Sebastian Huber <sebastian.huber@embedded-brains.de>

Browse Source 
* bsp_howto/console.t: Clarify interrupt transmit process.
	* user/concepts.t: Typo.
This commit is contained in:
Joel Sherrill
2009-01-29 14:57:28 +00:00
parent 897a86c454
commit 1813d94c7a
3 changed files with 17 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
doc/bsp_howto/console.t
View File

@@ -370,7 +370,15 @@ static void my_driver_interrupt_handler(
The @code{my_driver_interrupt_write} function is responsible for telling the
device that the @code{n} characters at @code{buf} are to be transmitted. The
return value may be arbitrary since it is not checked from Termios.
return value may be arbitrary since it is not checked from Termios. It is
guaranteed that @code{n} is greater than zero. This routine is invoked either
from task context with disabled interrupts to start a new transmission process
with exactly one character in case of an idle output state or from the
interrupt handler to refill the transmitter. If the routine is invoked to
start the transmit process the output state will become busy and Termios starts
to fill the output buffer. If the transmit interrupt arises before Termios was
able to fill the transmit buffer you will end up with one interrupt per
character.
@example
@group