Raspberrypi3: Mini UART driver
Niteesh
gsnb.gn at gmail.com
Wed Dec 25 09:50:04 UTC 2019
Just to make sure I am going in the right track.
I moved the uart register definitions to bsp/usart.h into a struct of
uint32_t called usart0_regs
here is git diff of usart.c after changing it to the latest console
interface.
diff --git a/bsps/arm/raspberrypi/console/usart.c
b/bsps/arm/raspberrypi/console/usart.c
index 25fb523621..b12f375a1c 100644
--- a/bsps/arm/raspberrypi/console/usart.c
+++ b/bsps/arm/raspberrypi/console/usart.c
@@ -47,6 +47,12 @@ static uint32_t usart_get_baud(const console_tbl *ct)
}
#endif
+typedef struct {
+ rtems_termios_device_context base;
+ const char *device_name;
+ volatile usart0_regs *regs;
+}uart0_context;
+
static void usart_set_baud(int minor, int baud)
{
/*
@@ -55,10 +61,17 @@ static void usart_set_baud(int minor, int baud)
return;
}
-static void usart_initialize(int minor)
+static volatile usart0_regs
*rpi_uart_get_regs(rtems_termios_device_context *base)
{
- unsigned int gpio_reg;
+ uart0_context *ctx;
+
+ ctx = (usart0_regs *) base;
+ return ctx->regs;
+}
+static void usart_initialize(rtems_termios_device_context *base)
+{
+ unsigned int gpio_reg;
/*
** Program GPIO pins for UART 0
*/
@@ -75,67 +88,81 @@ static void usart_initialize(int minor)
usart_delay(150);
BCM2835_REG(BCM2835_GPIO_GPPUDCLK0) = 0;
+ volatile uint32_t *uart_regs = rpi_uart_get_regs(base);
+
/*
** Init the PL011 UART
*/
- BCM2835_REG(BCM2835_UART0_CR) = 0;
- BCM2835_REG(BCM2835_UART0_ICR) = 0x7FF;
- BCM2835_REG(BCM2835_UART0_IMSC) = 0;
- BCM2835_REG(BCM2835_UART0_IBRD) = 1;
- BCM2835_REG(BCM2835_UART0_FBRD) = 40;
- BCM2835_REG(BCM2835_UART0_LCRH) = 0x70;
- BCM2835_REG(BCM2835_UART0_RSRECR) = 0;
-
- BCM2835_REG(BCM2835_UART0_CR) = 0x301;
-
- BCM2835_REG(BCM2835_UART0_IMSC) = BCM2835_UART0_IMSC_RX;
-
- usart_set_baud(minor, 115000);
+ uart_regs->cr = 0;
+ uart_regs->icr = 0x7ff;
+ uart_regs->imsc = 0;
+ uart_regs->ibrd = 1;
+ uart_regs->fbrd= 40;
+ uart_regs->lcrh= 0x70;
+ uart_regs->rsrecr= 0;
+ uart_regs->cr = 0x301;
+ uart_regs->imsc = BCM2835_UART0_IMSC_RX;
+ // usart_set_baud(minor, 115000);
}
-static int usart_first_open(int major, int minor, void *arg)
+static bool usart_first_open(
+ rtems_termios_tty *tty,
+ rtems_termios_device_context *base,
+ struct termios *term,
+ rtems_libio_open_close_args_t *args
+)
{
- rtems_libio_open_close_args_t *oc = (rtems_libio_open_close_args_t *)
arg;
- struct rtems_termios_tty *tty = (struct rtems_termios_tty *)
oc->iop->data1;
- const console_tbl *ct = Console_Port_Tbl [minor];
- console_data *cd = &Console_Port_Data [minor];
+ rtems_status_code sc;
+ uart0_context *ctx;
+ bool ok;
- cd->termios_data = tty;
- rtems_termios_set_initial_baud(tty, ct->ulClock);
+ ctx = (uart0_context *) base;
- return 0;
+ usart_initialize(base);
+
+ sc = rtems_termios_set_initial_baud(tty, USART0_DEFAULT_BAUD);
+ if ( sc != RTEMS_SUCCESSFUL ){
+ printk("Error setting the baud for termios\n");
+ return false;
+ }
}
-static int usart_last_close(int major, int minor, void *arg)
+static int usart_last_close(
+ rtems_termios_tty *tty,
+ rtems_termios_device_context *base,
+ rtems_termios_open_close_args_t *arg)
{
return 0;
}
-static int usart_read_polled(int minor)
+static int usart_read_polled(rtems_termios_device_context *base)
{
- if (minor == 0) {
- if (((BCM2835_REG(BCM2835_UART0_FR)) & BCM2835_UART0_FR_RXFE) == 0) {
- return((BCM2835_REG(BCM2835_UART0_DR)) & 0xFF );
- } else {
- return -1;
- }
- } else {
- printk("Unknown console minor number: %d\n", minor);
- return -1;
+ volatile usart0_regs *regs;
+
+ regs = rpi_uart_get_regs(base);
+
+ if ((regs->fr & BCM2835_UART0_FR_RXFE) == 0) {
+ return (regs->dr & 0xFF);
}
+
+ return -1;
}
-static void usart_write_polled(int minor, char c)
+static void usart_write_polled(rtems_termios_device_context *base, char c)
{
- while (1) {
- if ((BCM2835_REG(BCM2835_UART0_FR) & BCM2835_UART0_FR_TXFF) == 0)
- break;
- }
- BCM2835_REG(BCM2835_UART0_DR) = c;
+ volatile usart0_regs *regs;
+
+ regs = rpi_uart_get_regs(base);
+
+ while (1) {
+ if (((regs->fr) & BCM2835_UART0_FR_TXFF) == 0)
+ break;
+ }
+ regs->dr = c;
}
static ssize_t usart_write_support_polled(
- int minor,
+ rtems_termios_device_context *base,
const char *s,
size_t n
)
@@ -143,7 +170,7 @@ static ssize_t usart_write_support_polled(
ssize_t i = 0;
for (i = 0; i < n; ++i) {
- usart_write_polled(minor, s [i]);
+ usart_write_polled(base, s[i]);
}
return n;
@@ -154,14 +181,11 @@ static int usart_set_attributes(int minor, const
struct termios *term)
return -1;
}
-const console_fns bcm2835_usart_fns = {
- .deviceProbe = libchip_serial_default_probe,
- .deviceFirstOpen = usart_first_open,
- .deviceLastClose = usart_last_close,
- .deviceRead = usart_read_polled,
- .deviceWrite = usart_write_support_polled,
- .deviceInitialize = usart_initialize,
- .deviceWritePolled = usart_write_polled,
- .deviceSetAttributes = usart_set_attributes,
- .deviceOutputUsesInterrupts = false
-};
+const rtems_termios_device_handler bcm2835_uart0_handler_polled = {
+ .first_open = usart_first_open,
+ .last_close = usart_last_close,
+ .poll_read = usart_read_polled,
+ .set_attributes = usart_set_attributes,
+ .write = usart_write_support_polled,
+ .mode = TERMIOS_POLLED
+}
\ No newline at end of file
On Wed, Dec 25, 2019 at 12:36 AM Joel Sherrill <joel at rtems.org> wrote:
>
>
> On Tue, Dec 24, 2019, 12:19 PM Niteesh <gsnb.gn at gmail.com> wrote:
>
>> And also the register definitions are in raspberrpi.h file should I move
>> them to usart.h.
>>
>
> Sounds right if you mean bsp/usart.h
>
> I have a doubt we have a register field in device_context
>> typedef struct {
>>
>> rtems_termios_device_context base;
>>
>> const char *device_name;
>>
>> volatile some_chip_registers *regs;
>>
>> } my_driver_context;
>>
>> How does the reg field point to the correct memory location? for instance
>> in IMX BSP,
>> there is a struct with register field's but none of the define a memory
>> location?
>>
>
> Make sure the structure has volatiles and proper alignment. :)
>
>>
>> On Tue, Dec 24, 2019 at 11:37 PM Niteesh <gsnb.gn at gmail.com> wrote:
>>
>>> How to handle different serial devices? In other BSPs the uart devices
>>> are the same, so
>>> they were able to put it under a single array? But here we have 2 uarts
>>> and a FB?
>>>
>>>
>>> On Tue, Dec 24, 2019 at 8:18 PM Christian Mauderer <list at c-mauderer.de>
>>> wrote:
>>>
>>>> On 24/12/2019 12:06, Niteesh wrote:
>>>> > The current raspi console section is like this:
>>>> > The bsp_console_select in console_select.c is responsible for
>>>> selecting
>>>> > between uart and the framebuffer. It does so
>>>> > by setting the Console_port_minor.
>>>> > The console_config is responsible for output_char function.
>>>> > And other files are driver code.
>>>> > If rewriting, this would be my approach,
>>>> > Rewrite the bsp_console_select to set some kind of a variable like in
>>>> > IMX, then in console_initialize function
>>>> > link the right driver to /dev/console.
>>>> > Replace the console_tbl with the device_context and console_fns with
>>>> > termios_device_handlers and
>>>> > finally add in the console_initialization function.
>>>>
>>>> I agree that this would be a clean solution. So if you want you can do
>>>> that. But there might is a hurdle: As far as I understood you you only
>>>> have a Pi3? So you might have a hard time testing the changes. Maybe the
>>>> simulator could work.
>>>>
>>>> Another possibility could be to set the "Console_port_minor" to
>>>> something unused (for example -1). In that case you can define another
>>>> /dev/console.
>>>>
>>>> Best regards and merry Christmas (in case you celebrate)
>>>>
>>>> Christian
>>>>
>>>> >
>>>> > On Tue, Dec 24, 2019 at 2:13 PM Niteesh <gsnb.gn at gmail.com
>>>> > <mailto:gsnb.gn at gmail.com>> wrote:
>>>> >
>>>> > Thank you so much, for such a detailed answer. Now things make
>>>> > really good sense to me,
>>>> > going through the code now is just a breeze. But I still have one
>>>> > question
>>>> > for the newer driver interface is console_initialize the function
>>>> > which RTEMS calls while initializing
>>>> > the console? Which means I can't mess with the name right? It is
>>>> > similar to the main function, right?
>>>> >
>>>> > The current driver is a legacy one, how do you want me to proceed,
>>>> > shall I rewrite the legacy to a
>>>> > the new one, this is will be a great learning experience for me
>>>> also
>>>> > and we also get the BSP updated to the latest interface.
>>>> >
>>>> >
>>>> > On Tue, Dec 24, 2019 at 3:20 AM Christian Mauderer
>>>> > <list at c-mauderer.de <mailto:list at c-mauderer.de>> wrote:
>>>> >
>>>> > Hello Niteesh,
>>>> >
>>>> > quite a lot of questions. I'll try to answer them. Note that
>>>> it
>>>> > has been
>>>> > some time since I had a detailed look at that code so if
>>>> something I
>>>> > tell seems odd please don't hesitate to question it.
>>>> >
>>>> > Please note that in RTEMS their are more or less two "levels"
>>>> of
>>>> > support
>>>> > for a serial console:
>>>> >
>>>> > 1. A very basic polled system console (also known as
>>>> > "debug-console" in
>>>> > some BSPs). This one is used for printk and should work in
>>>> basically
>>>> > every case. It is used for critical system messages like
>>>> > printing the
>>>> > exception frame. For that a BSP has to provide a
>>>> > "BSP_output_char" function.
>>>> >
>>>> > 2. A full featured UART driver integrated into Termios. That
>>>> one
>>>> > will be
>>>> > used for all normal I/O on the UARTs.
>>>> >
>>>> > As far as I know the "console_tbl Console_Configuration_Ports"
>>>> > belongs
>>>> > to a table based legacy interface. It is handled in the file
>>>> > bsps/shared/dev/serial/legacy-console.c. I'm not sure whether
>>>> it is
>>>> > documented in the BSP guide because it shouldn't be used for
>>>> new
>>>> > BSPs.
>>>> > Same is true for the "major" and "minor" stuff: It's not
>>>> really
>>>> > used for
>>>> > new drivers.
>>>> >
>>>> > Newer drivers use the initialization that is described in the
>>>> manual
>>>> > that you have already found. Basically they use
>>>> > "rtems_termios_device_install" to register a new UART as
>>>> > "/dev/ttySomething". Some recent (ARM) BSPs that do that are
>>>> the
>>>> > imx or
>>>> > the atsam.
>>>> >
>>>> > The console that is used for stdin, stdout and stderr (printf,
>>>> > scanf,
>>>> > ...) is the one called "/dev/console" (defined in
>>>> > CONSOLE_DEVICE_NAME).
>>>> > For the legacy table based interface it's the one with the
>>>> index of
>>>> > "Console_Port_Minor".
>>>> >
>>>> >
>>>> > If you want to access any UART other than the one for stdin
>>>> and
>>>> > stdout
>>>> > you do that the same way like on Linux: Just use the "open"
>>>> > function on
>>>> > the "/dev/ttySomething" and use "read", "write" and simmilar
>>>> or use
>>>> > "fopen" together with "fread", "fwrite", "fprintf", ...
>>>> >
>>>> >
>>>> > "printf" (and family) is a function belonging to the C
>>>> library.
>>>> > In our
>>>> > case that's newlib. It will format your message and after
>>>> some other
>>>> > preprocessing will call the "write" function of the file that
>>>> is
>>>> > opened
>>>> > as stdout (which is "/dev/console" in the default case).
>>>> >
>>>> >
>>>> > I hope that I helped you with that explanation. Please feel
>>>> free
>>>> > to ask
>>>> > anything if it isn't clear.
>>>> >
>>>> > Best regards
>>>> >
>>>> > Christian
>>>> >
>>>> > On 23/12/2019 19:50, Niteesh wrote:
>>>> > > And finally, how does printf work? It is a macro? In that
>>>> > case, how does
>>>> > > any write to
>>>> > > a console work?
>>>> > >
>>>> > > On Tue, Dec 24, 2019 at 12:18 AM Niteesh <gsnb.gn at gmail.com
>>>> > <mailto:gsnb.gn at gmail.com>
>>>> > > <mailto:gsnb.gn at gmail.com <mailto:gsnb.gn at gmail.com>>>
>>>> wrote:
>>>> > >
>>>> > > Is the correct port minor number set during the
>>>> > initialization? What
>>>> > > is the application want's to
>>>> > > access some other port?
>>>> > >
>>>> > > On Tue, Dec 24, 2019 at 12:16 AM Niteesh
>>>> > <gsnb.gn at gmail.com <mailto:gsnb.gn at gmail.com>
>>>> > > <mailto:gsnb.gn at gmail.com <mailto:gsnb.gn at gmail.com>>>
>>>> wrote:
>>>> > >
>>>> > > I would like to clarify my doubts regarding the
>>>> > console driver.
>>>> > > I went through the documentation
>>>> > > for the console
>>>> > >
>>>> > driver
>>>> https://docs.rtems.org/branches/master/bsp-howto/console.html#introduction
>>>> .
>>>> > > But it is quite different from how some BSPs
>>>> initialize.
>>>> > > Correct me if I am wrong
>>>> > > The console_tbl contains the various entries of
>>>> serial
>>>> > ports.
>>>> > > The console_fns is a struct of function pointers,
>>>> > which point to
>>>> > > the BSP uart functions.
>>>> > > The BSP_output_char_function_type is what will be
>>>> > called for
>>>> > > printing a char on to the console.
>>>> > > How does RTEMS initialize the uart? It's seems not
>>>> to
>>>> > be same
>>>> > > for all BSPs.
>>>> > > The doc says that the driver's initialization
>>>> function
>>>> > is called
>>>> > > once during the rtems initialization process.
>>>> > > The console init function install the serial driver
>>>> using
>>>> > > rtems_termios_device_install but there seems to be
>>>> > > no such function in the raspberry pi? But there is a
>>>> > entry in
>>>> > > console_fns for init function, but then how does it
>>>> > > gets called?
>>>> > > And for BSP's with multiple serial's, the output
>>>> function
>>>> > > chooses the right serial using console_port_minor,
>>>> > > Is it during initialization?
>>>> > > What is the need for get and set register
>>>> functions?
>>>> > >
>>>> > > On Mon, Dec 23, 2019 at 1:04 AM Christian Mauderer
>>>> > > <list at c-mauderer.de <mailto:list at c-mauderer.de>
>>>> > <mailto:list at c-mauderer.de <mailto:list at c-mauderer.de>>>
>>>> wrote:
>>>> > >
>>>> > > On 22/12/2019 19:45, Joel Sherrill wrote:
>>>> > > >
>>>> > > >
>>>> > > > On Sun, Dec 22, 2019, 12:29 PM Niteesh
>>>> > <gsnb.gn at gmail.com <mailto:gsnb.gn at gmail.com>
>>>> > > <mailto:gsnb.gn at gmail.com <mailto:
>>>> gsnb.gn at gmail.com>>
>>>> > > > <mailto:gsnb.gn at gmail.com
>>>> > <mailto:gsnb.gn at gmail.com> <mailto:gsnb.gn at gmail.com
>>>> > <mailto:gsnb.gn at gmail.com>>>> wrote:
>>>> > > >
>>>> > > > On Sun, Dec 22, 2019 at 8:44 PM Christian
>>>> > Mauderer
>>>> > > > <list at c-mauderer.de
>>>> > <mailto:list at c-mauderer.de> <mailto:list at c-mauderer.de
>>>> > <mailto:list at c-mauderer.de>>
>>>> > > <mailto:list at c-mauderer.de
>>>> > <mailto:list at c-mauderer.de> <mailto:list at c-mauderer.de
>>>> > <mailto:list at c-mauderer.de>>>> wrote:
>>>> > > >
>>>> > > > Hello Niteesh,
>>>> > > >
>>>> > > > thanks for doing that work.
>>>> > > >
>>>> > > > On 22/12/2019 12:10, Niteesh wrote:
>>>> > > > > The rpi1 and rpi2 use the PL011
>>>> UART,
>>>> > whereas,
>>>> > > with RPI's
>>>> > > > equipped with
>>>> > > > > wireless/Bluetooth module, the
>>>> PL011 is
>>>> > > connected to the Bluetooth
>>>> > > > > module, and the mini UART is used as
>>>> > the primary
>>>> > > UART.
>>>> > > >
>>>> > > > In my opinion it would be great if you
>>>> > could use
>>>> > > the FDT to
>>>> > > > distinguish
>>>> > > > between the boards. That should allow
>>>> to add
>>>> > > raspberry 3 (and
>>>> > > > maybe 4)
>>>> > > > support without adding another BSP.
>>>> More
>>>> > BSPs mean
>>>> > > a bigger
>>>> > > > maintenance
>>>> > > > effort for the RTEMS community.
>>>> > > >
>>>> > > > Learning more about FDT is on my list for
>>>> a long
>>>> > > time. I would love
>>>> > > > to work on that
>>>> > > > but I have almost no exp with FDT's.
>>>> > > > But another thing could also be done, in
>>>> > > > raspberrypi/start/bspstart.c we get the
>>>> > revision and
>>>> > > > model of the board using the mailbox.
>>>> Every
>>>> > board has
>>>> > > a unique id,
>>>> > > > which we could use to initialize
>>>> > > > the BSP. But using FDT seems to be a more
>>>> > elegant
>>>> > > option, it is a
>>>> > > > lot of work I think, but we could take
>>>> > > > help from libbsd and linux I suppose. What
>>>> > do you think?
>>>> > > >
>>>> > > >
>>>> > > > I think there are almost always two steps to a
>>>> > project
>>>> > > like this: get it
>>>> > > > to work and make it nice. :)
>>>> > > >
>>>> > > > If you fix the startup code to read the board
>>>> > revision and
>>>> > > memory size,
>>>> > > > you can get a working BSP that dynamically
>>>> > adapts to the
>>>> > > models and
>>>> > > > memory variations with minimal modifications.
>>>> If
>>>> > you want
>>>> > > to then
>>>> > > > convert the BSP to FDT, it will be a LOT
>>>> easier
>>>> > to debug
>>>> > > with a working BSP.
>>>> > > >
>>>> > > > Plus you may be able to identify every
>>>> variation
>>>> > point
>>>> > > based on just the
>>>> > > > model info. Then FDT is just a matter of
>>>> > switching the
>>>> > > source of
>>>> > > > some/all of the info.
>>>> > > >
>>>> > > > That would be my work plan anyway.
>>>> > >
>>>> > > I agree with Joel that a secure development
>>>> basis
>>>> > (also
>>>> > > known as "hack")
>>>> > > as a first step is a good idea. You maybe even
>>>> > just make the
>>>> > > mini UART
>>>> > > the default driver while you are developing.
>>>> Then
>>>> > you can be
>>>> > > sure that
>>>> > > you have the right driver.
>>>> > >
>>>> > > As soon as that works you can either change to
>>>> the
>>>> > revision
>>>> > > method or
>>>> > > (better) to the FDT one and after that the
>>>> patches
>>>> > can be
>>>> > > merged. Using
>>>> > > the FDT isn't that complicated. Basically you
>>>> > search for a
>>>> > > node based on
>>>> > > different parameters. For an example you can
>>>> take
>>>> > a look at
>>>> > > the imx BSP.
>>>> > > In imx_uart_probe
>>>> > (bsps/arm/imx/console/console-config.c) a
>>>> > > fdt node is
>>>> > > searched and based on that a UART driver is
>>>> used.
>>>> > But again:
>>>> > > Follow
>>>> > > Joels suggestion to start simple and secure.
>>>> > >
>>>> > > >
>>>> > > > >
>>>> > > > >
>>>> > > >
>>>> > >
>>>> >
>>>> https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
>>>> > > > > But from the above doc (PAGE 10),
>>>> the
>>>> > mini uart
>>>> > > has 16550 like
>>>> > > > registers
>>>> > > > > and RTEMS already has the driver
>>>> for it
>>>> > > > > bsps/shared/dev/serial/ns16550.c.
>>>> But
>>>> > I am not
>>>> > > sure how
>>>> > > > compatible they
>>>> > > > > are? Should a new driver be
>>>> > implemented from
>>>> > > scratch or use
>>>> > > > ns16550 if
>>>> > > > > possible?
>>>> > > >
>>>> > > > In general it's better to re-use
>>>> > existing code.
>>>> > > That has multiple
>>>> > > > advantages:
>>>> > > >
>>>> > > > - It reduces the maintenance effort.
>>>> > Fewer code
>>>> > > means fewer work.
>>>> > > > - If you have multiple driver for the
>>>> > same or
>>>> > > similar hardware
>>>> > > > it can
>>>> > > > happen that a bug is fixed in one but
>>>> > not the other.
>>>> > > > - It's simpler to find a hardware to
>>>> > test changes.
>>>> > > > - The driver becomes more universal
>>>> with
>>>> > every new
>>>> > > supported
>>>> > > > hardware.
>>>> > > > That increases the chance that it fits
>>>> > the next
>>>> > > new hardware.
>>>> > > >
>>>> > > > I'm sure there are some more if you
>>>> ask
>>>> > someone else.
>>>> > > >
>>>> > > > I do understand the issues, I just spent
>>>> > some time
>>>> > > reading the
>>>> > > > driver code.
>>>> > > > I think we could most probably use it. I
>>>> > will take a
>>>> > > closer look and
>>>> > > > will update.
>>>> > > >
>>>> > >
>>>> > > Great.
>>>> > >
>>>> > > >
>>>> > > >
>>>> > > > >
>>>> > > > > Also, the core clock on which the
>>>> > PL011 is based
>>>> > > on is changed
>>>> > > > in rpi3.
>>>> > > > > Rpi1 and 2 use 250Mhz as the default
>>>> > clock but
>>>> > > it was changed
>>>> > > > to 400Mhz
>>>> > > > > in Rpi3 and newer
>>>> > > >
>>>> > > > Again: Would be great if that could be
>>>> > adapted
>>>> > > based on FDT or by
>>>> > > > reading the right registers.
>>>> > > >
>>>> > > > >
>>>> > > > > Few differences between PL011 and
>>>> Mini
>>>> > uart
>>>> > > > > The mini UART has smaller FIFOs.
>>>> > Combined with
>>>> > > the lack of
>>>> > > > flow control,
>>>> > > > > this makes it more prone to losing
>>>> > characters at
>>>> > > higher baud
>>>> > > > rates. It
>>>> > > > > is also generally less capable than
>>>> > the PL011,
>>>> > > mainly due to
>>>> > > > its baud
>>>> > > > > rate link to the VPU clock speed.
>>>> > > >
>>>> > > > That shouldn't really be a problem for
>>>> > the system
>>>> > > console.
>>>> > > >
>>>> > > > >
>>>> > > > > The particular deficiencies of the
>>>> > mini UART
>>>> > > compared to the
>>>> > > > PL011 are :
>>>> > > > >
>>>> > > > > No break detection
>>>> > > > > No framing errors detection
>>>> > > > > No parity bit
>>>> > > > > No receive timeout interrupt
>>>> > > > > No DCD, DSR, DTR or RI signals
>>>> > > > >
>>>> > > >
>>>> > > >
>>>> _______________________________________________
>>>> > > > devel mailing list
>>>> > > > devel at rtems.org <mailto:devel at rtems.org>
>>>> > <mailto:devel at rtems.org <mailto:devel at rtems.org>>
>>>> > > <mailto:devel at rtems.org <mailto:devel at rtems.org
>>>> >
>>>> > <mailto:devel at rtems.org <mailto:devel at rtems.org>>>
>>>> > > >
>>>> http://lists.rtems.org/mailman/listinfo/devel
>>>> > > >
>>>> > >
>>>> >
>>>>
>>>
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