On Monday 23 February 2009 22:07, Anand Palaniswamy wrote: > my language is bad because its not my mother tongue
and its the way
> of short form we speak
Please speak for yourself. We (most Indians i know) DO NOT "speak" or
write in crappy sms lingo irrespective of ones mother tongue. And
nobody is grumbling about grammar, people are complaining about
spelling of simple words like you != u your != ur we != v please !pls.
When speaking to an unknown audience one should stick to the
dictionary.
--
Rgds
JTD
Reply by Robert Adsett●February 23, 20092009-02-23
Paul Curtis wrote: > That's the inter-frame gap, depends upon whether
it is 10base or 100base. I
> believe the minimum is 96 bit times (the 12 bytes in the calculation
below).
Ah, I didn't see the interframe. Apparently I've been following
Ralph's
references.
From the Divided by a Common Language File (Edited to protect the guilty)
ME - "I'd like to get Price and delivery for connector Part # XXXXX"
Dist./Rep - "$X.XX Lead time 37 days"
ME - "Anything we can do about lead time? 37 days seems a bit high."
Dist./Rep - "that is the lead time given because our stock is live....
we currently have stock."
Reply by Paul Curtis●February 23, 20092009-02-23
That's the inter-frame gap, depends upon whether it is 10base or 100base.
I
believe the minimum is 96 bit times (the 12 bytes in the calculation below).
> -----Original Message-----
> From: l... [mailto:l...] On Behalf Of > s...@aeolusdevelopment.com
> Sent: 23 February 2009 18:44
> To: l...; l...
> Subject: RE: [lpc2000] transfer speed of data using uipstack and free rtos
>
> Is there not a quiet period required between packets as well?
>
> Robert
>
> Original Message:
> -----------------
> From: Paul Curtis p...@rowley.co.uk
> Date: Mon, 23 Feb 2009 14:41:39 -0000
> To: l...
> Subject: RE: [lpc2000] transfer speed of data using uipstack and free rtos
> Hi,
>
> > 3. You have always an overhead. Even with raw-ethernet you have one of
> > 18 bytes + 8 byte preamble, i.e. 1.7%.
>
> More than that, in fact. I calculate (preamble, 2 MAC addresses,
> Ethertype,
> , CRC, interframe gap) = 8 + 12 + 2 + 4 + 12 = 38 bytes... And
> then you need to put IP headers in the payload...
>
> --
> Paul Curtis, Rowley Associates Ltd http://www.rowley.co.uk
> CrossWorks for ARM, MSP430, AVR, MAXQ, and now Cortex-M3 processors
>
Reply by "sub...@aeolusdevelopment.com"●February 23, 20092009-02-23
Is there not a quiet period required between packets as well?
Robert
Original Message:
-----------------
From: Paul Curtis p...@rowley.co.uk
Date: Mon, 23 Feb 2009 14:41:39 -0000
To: l...
Subject: RE: [lpc2000] transfer speed of data using uipstack and free rtos
Hi,
> 3. You have always an overhead. Even with
raw-ethernet you have one of
> 18 bytes + 8 byte preamble, i.e. 1.7%.
More than that, in fact. I calculate (preamble, 2 MAC addresses, Ethertype,
, CRC, interframe gap) = 8 + 12 + 2 + 4 + 12 = 38 bytes... And
then you need to put IP headers in the payload...
--
Paul Curtis, Rowley Associates Ltd http://www.rowley.co.uk
CrossWorks for ARM, MSP430, AVR, MAXQ, and now Cortex-M3 processors
Reply by Paul Curtis●February 23, 20092009-02-23
Hi Richard,
> Its what's known in Blighty as WKS (Wanky Kids
Speak).
>
> (yes I'm deliberately using terms not everybody would understand)
Have you seen the latest Gesture-based remote control for TVs? I guess the
gesture for getting to Channel 69 is quite obvious?
--
Paul Curtis, Rowley Associates Ltd http://www.rowley.co.uk
CrossWorks for ARM, MSP430, AVR, MAXQ, and now Cortex-M3 processors
Reply by 42Bastian●February 23, 20092009-02-23
Anand Palaniswamy schrieb: > my language is bad because its not my mother tongue
and its the way of short form we speak
Neither is it mine. But you should have learned in your mother language
that speaking and writing is different.
But, heck, I get int the troll-trap every time. My &&%"& filter is not
working.
--
42Bastian
Note: SPAM-only account, direct mail to bs42@...
Reply by "FreeRTOS.org Info"●February 23, 20092009-02-23
> my language is bad because its not my mother tongue
and its
> the way of short form we speak Its what's known in Blighty as WKS (Wanky Kids Speak).
(yes I'm deliberately using terms not everybody would understand)
Regards,
Richard.
+ http://www.FreeRTOS.org
Designed for Microcontrollers. More than 7000 downloads per month.
+ http://www.SafeRTOS.com
Certified by T as meeting the requirements for safety related systems.
Reply by Anand Palaniswamy●February 23, 20092009-02-23
hi the data is transfered through UDP prtocol so there is no need for ACK ..only
TCP requires ACK
________________________________
From: paulkimelman
To: l...
Sent: Monday, 23 February, 2009 9:07:15 PM
Subject: [lpc2000] Re: transfer speed of data using uipstack and free rtos
--- In lpc2000@yahoogroups .com, "Paul Curtis" wrote: >
> Hi,
>
> > 3. You have always an overhead. Even with raw-ethernet you have one of
> > 18 bytes + 8 byte preamble, i.e. 1.7%.
>
> More than that, in fact. I calculate (preamble, 2 MAC addresses, Ethertype, > , CRC, interframe gap) = 8 + 12 + 2 + 4 + 12
= 38 bytes... And
> then you need to put IP headers in the payload...
Yes, the header overhead would certainly limit the data rate. Of
course, the poster may have been talking about bytes on the line, but
even then, the preamble in ENET (a string of a recognizable bit
pattern) takes overhead too.
In any case, uIP cannot possibly get anywhere near that with TCP/IP
because it does not support windowing. TCP/IP is very slow to send one
packet because you have to wait for the ACK. It can be fast to send a
huge block of data by sending out 5 packets and then sending more as
ACKs come back. But, even then, it is hard to get near to line speed.
uIP does not do this windowing, so it will send one packet and block
write until the ACK. Then, it sends the next. So, the time to send
large amounts of data is severely impacted. LwIP does allow windowing,
but how much depends on the pool size.
Reply by Anand Palaniswamy●February 23, 20092009-02-23
my language is bad because its not my mother tongue and its the way of short
form we speak
ya the calculation is correct i just said the approximate value of 11.7
MByte/sec as 12MByte/sec k va
ya i know its really impossible in the practical world atleast we can transfer
the data at 80 Mbit/sec - 90 Mbits/sec
________________________________
From: 42Bastian
To: l...
Sent: Monday, 23 February, 2009 7:29:27 PM
Subject: Re: [lpc2000] transfer speed of data using uipstack and free rtos
Anand Palaniswamy schrieb:
1. Your language is bad (it is "your" not "ur").
> ur very bad in ur calculations 12 MBytes/sec is
actualy 100 Mbits/sec
2. Your math as well:
12MB = 12*1024*1024* 8 = 100663296 which is more than the 100Mib/s of the
ethernet
3. You have always an overhead. Even with raw-ethernet you have one of
18 bytes + 8 byte preamble, i.e. 1.7%.
--- In l..., "Paul Curtis" wrote: >
> Hi,
>
> > 3. You have always an overhead. Even with raw-ethernet you have one of
> > 18 bytes + 8 byte preamble, i.e. 1.7%.
>
> More than that, in fact. I calculate (preamble, 2 MAC addresses, Ethertype, > , CRC, interframe gap) = 8 + 12 + 2 + 4 + 12
= 38 bytes... And
> then you need to put IP headers in the payload...
Yes, the header overhead would certainly limit the data rate. Of
course, the poster may have been talking about bytes on the line, but
even then, the preamble in ENET (a string of a recognizable bit
pattern) takes overhead too.
In any case, uIP cannot possibly get anywhere near that with TCP/IP
because it does not support windowing. TCP/IP is very slow to send one
packet because you have to wait for the ACK. It can be fast to send a
huge block of data by sending out 5 packets and then sending more as
ACKs come back. But, even then, it is hard to get near to line speed.
uIP does not do this windowing, so it will send one packet and block
write until the ACK. Then, it sends the next. So, the time to send
large amounts of data is severely impacted. LwIP does allow windowing,
but how much depends on the pool size.
