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Fw: strange UART behaviour while running ecos
- From: tayyaba azeem <u04175 at yahoo dot com>
- To: "ecos-discuss at ecos dot sourceware dot org" <ecos-discuss at ecos dot sourceware dot org>
- Date: Thu, 15 Mar 2012 21:46:42 -0700 (PDT)
- Subject: [ECOS] Fw: strange UART behaviour while running ecos
- References: <1331824622.13037.YahooMailNeo@web160301.mail.bf1.yahoo.com>
- Reply-to: tayyaba azeem <u04175 at yahoo dot com>
>Hi all,
>?
>I am kind of new to leon3 but I have successfully run ecos from prom and have also accessed GPIO via a simple C application. I am using ML501 board. And now I was trying to send and receive data via uart but I observed a strange behavior that data does get transmitted and received over uart but it's not what I send! To elaborate, I've written a simple code which only transmits a byte when it receives a byte but if I send 0x36 to PC I receive 0xf5 and no matter what else I send I receive 0xf6 only on my PC. But the strange thing I've found is that if I transmit more than one byte from leon3 (say 2 or 3 bytes data) I receive infinite bytes on my PC and they only stop once I reset the CPU or switch the board off.
>?
>Here's a summary of what I have tried to troubleshoot just to help anyone who tries to diagnose the problem.
>?
>I am using ecos-rep-1.0.9 and have booted from rom and have accessed an led via GPIO successfully so I feel boot code is fine.
>My clock frequency is 40 MHz and baud rate 38400.
>I have checked the APBUART initialization in ecos with baudrate and flow control enabled and have gone through the APBUART initialization code in the repository couldn't find any bug there though.
>But to be on the safe side I have initialized the uart myself again in my c file (i have enabled receive and transmit and flow control and disabled DB bit) the scaler register is 81hex.?
>My fifosize is 4 bytes but nothing has helped so far.
>Moreover, today I tried to send/receive data over uart using grmon for this?I wrote:
>?
>char c;
>scanf("%c", &c);
>printf("%c", c);
>?
>but the character was never printed not even in TSIM.
>?
>Any help to get around this problem is highly appreciated.?
>?
>Best Regards,
>Tayyaba Azeem?
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