- the infinite timeout value is again represented by a special value
(not a special timer ID), but this time it's a non-negative value
- all timers in the UART module default to the system timer
- all timers in the TMR module default to the system timer
- implemented a generic system timer mechanism that can be used in
conjunction with a timer interrupt.
- implemented system timers on LM3S (tested) and STM32 (not tested).
Both are based on the Cortex M3 SysTick timer.
Previously, if you set a frequency value ten times the PWM clock
frequency, it would calculate a period of 0 and return foo/0, which
gives -1 on AVR32. With this change, everything > pwmclk sets and
returns a frequency of pwmclk.
Previously, pwm.setup() would set a frequency equal to or less
than the one asked for, and report an integer less than or equal
to the actual frequency set. This change makes it set the closest
available frequency and report the closest integer to that.
Previously, you could ask for a PWM frequency of 0 and negative
duty cycles, and each platform would do a different thing: failing
or setting some random values. This change replaces such values
with the minimum, the same way that duty is bounded to 100.
- added explicit support for the system timer in common_tmr.c
- all the functions in the tmr module will now use the system timer
by default (if no id is specified)
- infinite timeout will be specified by using a special timer ID
rather than using negative timeout values (this allows the timer
data type to be unsigned and increases the timer range)
THe MAXUPVALUES was reduced to reduce stack and RAM usage, but turns out
to create incomprehensible erorrs for beginners when they use more than
10 global variables ina function.
This change puts is back tot eh Lua defualt, which uses 100 bytes more
RAM when parsnig functions, or 200 if they have nested functions.
This seems less bad than throwing incomprehensible errors when beginners
code the sort of things that beginners always code.
==================
From: Raimondas Sasnauskas <raimondas.sasnauskas@cs.rwth-aachen.de>
Date: Sun, Sep 20, 2009 at 1:29 PM
Subject: Re: RE: Re: RE: Re: Re: RE: Bug (?) in uip TCP/IP stack: lost SYNACK causes connection reset
OK, here I'm proposing the following patch (see git diff attached).
Again the problem we face here is the subsequent SYN arriving in
UIP_SYN_RCVD state after the SYNACK packet was lost. First, to avoid
other issues, suggest to reset any _active_ connection where a SYN
arrives in a state != UIP_SYN_RCVD.
==================
This is a combination of the patch submitted by Raimondas Sasnauskas and
the patch applied by Oliver Schmidt to Contiki
===================
Original bug report
===================
From: Raimondas Sasnauskas
<raimondas.sasnauskas@cs.rwth-aachen.de>
Subject: Bug (?) in uip TCP/IP stack: lost SYNACK causes
connection reset
Date: 2009-09-02 19:07:51 GMT
Hi all,
I've found the following issue in the TCP (UIP_ACTIVE_OPEN)
connection establishment phase leading to connection failure.
This happens whe the SYNACK packet gets lost during the TCP
3-way handshake.
Client: SYN
Server: SYNACK (this packet gets lost)
Client: SYN (retransmission)
Server: ACK (<-- server thinks it's data?)
Client: RESET (correct, no SYNACK received yet)
Server: ABORT (got reset, aborting connection)
I do not have a patch/workaround yet, but I think that
correctly handling incoming TCP_SYN packets in UIP_SYN_RCVD
state would fix this issue.
http://article.gmane.org/gmane.network.uip.user/1506
Here's the content of the patch (so it can be more easily
discussed if need be). What basically happens is uip_len and
uip_slen never get reset to 0 when calling the poll handler.
Here's an example of how things go wrong:
Let's say you get some new incoming data (uip_newdata()), your
application handler processes the new data and sends something
out (thus setting uip_slen). Back in the main loop again, you
poll a connection. uip_slen is still set from the last send and
if your poll handler doesn't send out something new, uip ends up
just sending out the exact same data on the now polled
connection. In every other applicable case, uip_len and
uip_slen get reset, but for whatever reason this one just got
missed...
http://article.gmane.org/gmane.network.uip.user/1312
I have been working on implementing a port to the atmel
ATMega128 and I have noticed that sending UDP packets does not
work (the transferred data is always 0).
A look into the code reveals that in uip.c, the address of
uip_appdata gets set incorrectly.
Somewhere around line 1159 the code needs to be changed:
--- uip_appdata = &uip_buf[UIP_LLH_LEN + UIP_IPTCPH_LEN];
+++ uip_appdata = &uip_buf[UIP_LLH_LEN + UIP_IPUDPH_LEN];
http://article.gmane.org/gmane.network.uip.user/68
i just saw that the stats taking in uip is missing entries for udp
receive and
transmit.
To fix this insert a UIP_STAT after the udp_found label:
udp_found:
+ UIP_STAT(++uip_stat.udp.recv);
And a UIP_STAT before the goto ip_send_nolen instruction:
+ UIP_STAT(++uip_stat.udp.sent);
goto ip_send_nolen;
The separate dependency generation step from the Lua build system
was not needed, now the dependencies are generated at the same time
as the object files.
The new LCD firmware doesn't need the caller to wait after each command:
it stretches the clock instead. Actually, it works at 68kHz too, but
there is a non-working range from 55 to 66kHz.
We set it to 50000Hz to have reliable operation and allow for clock drift.
We just changed LCD command 0 from a no-op to a speciall-recognized
hardware reset. This is essential because the LCD controller's reset line
is not connected to the AVR32's reset line, so if the AVR32 is reset,
the LCD is left in an unknown, possible unusable, state.
The old slave addresses, F2, F3, F6, F7 are reserved for 10-bit
I2C addressing. This changes them to values that are least likely
to conflist with other devices: 7C-7F are registered to two LCD display
devices.
In integer math, floor() and ceil() give the same value, but
having them included in the integer library as functions that return
their argument allows you more easily to write code that works unchanged
in both integer and floating point versions of Lua.
The code for the bitbanger, taken from wikipedia, in turn taken from
http://www.nctutwt.net/wiki/doku.php?id=wiki:summer2010:i2c
does a STOP condition by raising SCL and immediately raising SDA, but
in the I2C spec, there is a minimum STOP setup time of 4ms between these
transitions (I2C spec, doc UM10204, table 6/figure 27, pp.37-38).
Similarly, a repeated START has a setup time of minimum 4.7us between
SCL going high and SDA going low, which the code did not contain.
This patch inserts these delays to conform better to the I2C spec,
even though all tested devices "seemed to work" without them.
platform_pwm_op( id, op, data ) did four unrelated tasks, switching on the
"op" parameter:
op==PLATFORM_PWM_OP_SET_CLOCK took a frequency and returned a frequency
op==PLATFORM_PWM_OP_GET_CLOCK took nothing returned a frequency
op==PLATFORM_PWM_OP_START and _STOP both took nothing and returned nothing
this patch replaces it with:
clock = platform_pwm_set_clock( id, clock)
clock = platform_pwm_get_clock( id )
platform_pwm_start( id ) and
platform_pwm_stop( id )
with resulting clarity in the documentation and smaller, faster code.
This does not affect the Lau interface.
