From: "Richard Rauch" <rrauch@itrgmbh.de>
To: "'Michael W. Ellis'" <mellis@pesa.com>,
<ecos-discuss@ecos.sourceware.org>
Subject: AW: [ECOS] cyg_flag_timed_wait doesn't seem to work as expected
Date: Fri, 27 May 2016 15:53:00 -0000 [thread overview]
Message-ID: <01fb01d1b82f$e61c8ee0$b255aca0$@itrgmbh.de> (raw)
In-Reply-To: <07FFDDED6CBCCE4E9FBD46AEC3EBFD4F02C50652@exchange>
Hi Michael,
do you initialize the flags somewhere with cyg_flag_init() ?
This initialisation needs to be made before the first access of the event
flag variable.
Best Regards
Richard
www.itrgmbh.com
> -----Ursprüngliche Nachricht-----
> Von: ecos-discuss-owner@ecos.sourceware.org [mailto:ecos-discuss-
> owner@ecos.sourceware.org] Im Auftrag von Michael W. Ellis
> Gesendet: Freitag, 27. Mai 2016 15:31
> An: ecos-discuss@ecos.sourceware.org
> Betreff: [ECOS] cyg_flag_timed_wait doesn't seem to work as expected
>
> I'm running an old version of eCos (2.0.98) from eCosCentric and I'm
> attempting to use cyg_flag_timed_wait to periodically update a display
(see
> code, below). My event flag variable g_flags is initialized elsewhere
before
> this thread is created. Other threads access the same event flag but use
their
> own bits within the flag.
>
> My problem is with the timed wait behavior of the event flag. At startup
I
> see an initial wait of 30 seconds before the first display update occurs,
but
> the update occurs continually after the initial timeout. The local
variable
> flags always reads 0, indicating timeout has occurred. My understanding
is
> that calling cyg_flag_timed_wait at the top of the loop restarts the
timer, but
> this does not seem to be the case. What am I missing here? Is there
> something I must do to clear the timeout event?
>
> Variable allocation and initialization:
> static cyg_flag_t g_flags; //
thread sync event flags
> cyg_flag_init(&g_flags); //
init thread sync flag
>
>
> // ogDisplayThread - update display
> static void ogDisplayThread(cyg_addrword_t data) {
> diag_printf("Entering ogDisplayThread...\r\n");
>
> cyg_flag_setbits(&g_flags, OG_FLAG_DISP_RDY); //
say this
> thread is ready
>
> while (1)
> {
> cyg_flag_value_t flags;
>
> flags = cyg_flag_timed_wait(&g_flags, //
timed wait
> OG_FLAG_DISP_EXIT, //
wait for EXIT flag or
> timeout
> CYG_FLAG_WAITMODE_AND,
> 3000); //
30 second timeout
>
> diag_printf("ogDisplayThread flag = %08X\r\n", flags);
>
> if (flags & OG_FLAG_DISP_EXIT) //
if EXIT event
> occurred
> {
> diag_printf("Exiting ogDisplayThread\r\n");
>
> cyg_flag_maskbits(&g_flags, //
say this thread is no
> longer ready
> OG_FLAG_DISP_RDY|OG_FLAG_DISP_EXIT);
>
> cyg_thread_exit(); //
and exit thread
> }
> else if (!flags) //
if timeout occurred (normal
> condition)
> {
> diag_printf("ogDisplayThread sending data\r\n");
> ogp_msg_t *msg;
>
> // send IP address
> if (NULL == (msg = malloc(sizeof(ogp_msg_t)))) //
allocate a
> message buffer
> diag_printf("ogDisplayThread malloc error\r\n");
> else
> {
> msg->sync = htonl(OGP_SYNC_WORD); //
build message
> msg->src = LOCAL_CMD_SRC;
> msg->dst = LOCAL_CMD_DST_SET_IPADDR;
> msg->mtype = LOCAL_CMD_MTYPE;
> api_eth_get_ip(msg->data, 16); //
get IP address string
> msg->len = htons(strlen(msg->data)+1); //
set length
> ogpPutTxQ(msg); //
send message
> }
> }
> else //
should never get here
> diag_printf("ogDisplayThread unexpected event flag\r\n");
> }
> }
>
> Debug output (continual after 30 seconds):
> ogDisplayThread flag = 00000000
> ogDisplayThread sending data
> ogDisplayThread flag = 00000000
> ogDisplayThread sending data
> ogDisplayThread flag = 00000000
> ogDisplayThread sending data
> ogDisplayThread flag = 00000000
> ogDisplayThread sending data
> ogDisplayThread flag = 00000000
> ogDisplayThread sending data
> ogDisplayThread flag = 00000000
> ogDisplayThread sending data
> ogDisplayThread flag = 00000000
> ogDisplayThread sending data
>
>
> Thanks,
> Michael
>
>
> --
> Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos
> and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss
next prev parent reply other threads:[~2016-05-27 15:53 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-27 13:29 Michael W. Ellis
2016-05-27 15:53 ` Richard Rauch [this message]
2016-05-27 16:31 ` Nick Garnett
2016-05-27 20:46 ` Michael W. Ellis
2016-06-16 13:26 ` [ECOS] eCos Configuration Tool clewan and rebuild Michael W. Ellis
2016-06-16 17:09 ` [ECOS] " Grant Edwards
2016-06-16 21:18 ` Michael W. Ellis
2016-06-16 21:41 ` Grant Edwards
2016-06-16 23:05 ` Alex Schuilenburg
2016-06-17 4:05 ` AW: " Richard Rauch
2016-06-17 10:10 ` Alex Schuilenburg
2016-06-18 12:01 ` AW: " Richard Rauch
2016-06-18 13:20 ` Alex Schuilenburg
2016-06-30 14:53 ` [ECOS] Input from debug console Michael W. Ellis
2016-06-30 16:01 ` Michael W. Ellis
2016-06-30 16:09 ` Evgeniy Dushistov
2016-06-30 17:52 ` [ECOS] " Grant Edwards
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