On 06/04/13 23:37, bm wrote:
"dennis@home" wrote in message
eb.com...
On 06/04/2013 13:05, Steve Firth wrote:
"dennis@home" wrote:
[snip]

In professional circles serial links are always measured in bits per
second. Mb/s and MB/s are the same.

Horse****.

There are people that try to insist that Mb/s and MB/s are different.

Yes, people who know what they are talking about. Clearly this group
excludes you.

In reality professionals now write bits/s or bytes/s so there is no
misunderstanding.

How would you know what professionals do Pennis?



Well its easy enough to prove you talk cr@p.

For instance Cisco use 100MB when they refer to 100 Megabit switches,

Where did you see that Dennis?


"It was a strange dream...."

http://www.youtube.com/watch?v=m_PHDXdgZTI

snip




--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

"The Natural Philosopher" wrote in message
...
On 06/04/13 23:37, bm wrote:
"dennis@home" wrote in message
eb.com...
On 06/04/2013 13:05, Steve Firth wrote:
"dennis@home" wrote:
[snip]

In professional circles serial links are always measured in bits per
second. Mb/s and MB/s are the same.

Horse****.

There are people that try to insist that Mb/s and MB/s are different.

Yes, people who know what they are talking about. Clearly this group
excludes you.

In reality professionals now write bits/s or bytes/s so there is no
misunderstanding.

How would you know what professionals do Pennis?



Well its easy enough to prove you talk cr@p.

For instance Cisco use 100MB when they refer to 100 Megabit switches,

Where did you see that Dennis?


"It was a strange dream...."

http://www.youtube.com/watch?v=m_PHDXdgZTI


I prefer this one -
http://www.youtube.com/watch?v=vP1QNz-9tf0

On 07/04/13 00:27, bm wrote:
"The Natural Philosopher" wrote in message
...
On 06/04/13 23:37, bm wrote:
"dennis@home" wrote in message
eb.com...
On 06/04/2013 13:05, Steve Firth wrote:
"dennis@home" wrote:
[snip]

In professional circles serial links are always measured in bits per
second. Mb/s and MB/s are the same.

Horse****.

There are people that try to insist that Mb/s and MB/s are different.

Yes, people who know what they are talking about. Clearly this group
excludes you.

In reality professionals now write bits/s or bytes/s so there is no
misunderstanding.

How would you know what professionals do Pennis?



Well its easy enough to prove you talk cr@p.

For instance Cisco use 100MB when they refer to 100 Megabit switches,

Where did you see that Dennis?


"It was a strange dream...."

http://www.youtube.com/watch?v=m_PHDXdgZTI


I prefer this one -
http://www.youtube.com/watch?v=vP1QNz-9tf0


yes, but you aren't dennis.in.a.home.

--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

On 06/04/2013 23:37, bm wrote:
"dennis@home" wrote in message
eb.com...
On 06/04/2013 13:05, Steve Firth wrote:
"dennis@home" wrote:
[snip]

In professional circles serial links are always measured in bits per
second. Mb/s and MB/s are the same.

Horse****.

There are people that try to insist that Mb/s and MB/s are different.

Yes, people who know what they are talking about. Clearly this group
excludes you.

In reality professionals now write bits/s or bytes/s so there is no
misunderstanding.

How would you know what professionals do Pennis?



Well its easy enough to prove you talk cr@p.

For instance Cisco use 100MB when they refer to 100 Megabit switches,

Where did you see that Dennis?

snip



Just the first product I clicked on.

There is no standard for MB and Mb so anyone that wants to avoid
ambiguity spells it out.

If you think there is a universal standard then you can probably get a
job at NASA and crash a space probe or two.

On Sun, 07 Apr 2013 16:44:40 +0100, dennis@home wrote:

On 06/04/2013 23:37, bm wrote:
"dennis@home" wrote in message
eb.com...
On 06/04/2013 13:05, Steve Firth wrote:
"dennis@home" wrote:
[snip]

In professional circles serial links are always measured in bits per
second. Mb/s and MB/s are the same.

Horse****.

There are people that try to insist that Mb/s and MB/s are
different.

Yes, people who know what they are talking about. Clearly this group
excludes you.

In reality professionals now write bits/s or bytes/s so there is no
misunderstanding.

How would you know what professionals do Pennis?



Well its easy enough to prove you talk cr@p.

For instance Cisco use 100MB when they refer to 100 Megabit switches,

Where did you see that Dennis?

snip



Just the first product I clicked on.

There is no standard for MB and Mb so anyone that wants to avoid
ambiguity spells it out.

Apart from SI (for the prefix) and IEEE 1541 (for the 'B' or 'b'). Stop
wriggling, dennis.



--
Use the BIG mirror service in the UK: http://www.mirrorservice.org
My posts (including this one) are my copyright and if @diy_forums on
Twitter wish to tweet them they can pay me £30 a post
*lightning surge protection* - a w_tom conductor

On 07/04/2013 18:32, Bob Eager wrote:
On Sun, 07 Apr 2013 16:44:40 +0100, dennis@home wrote:

On 06/04/2013 23:37, bm wrote:
"dennis@home" wrote in message
eb.com...
On 06/04/2013 13:05, Steve Firth wrote:
"dennis@home" wrote:
[snip]

In professional circles serial links are always measured in bits per
second. Mb/s and MB/s are the same.

Horse****.

There are people that try to insist that Mb/s and MB/s are
different.

Yes, people who know what they are talking about. Clearly this group
excludes you.

In reality professionals now write bits/s or bytes/s so there is no
misunderstanding.

How would you know what professionals do Pennis?



Well its easy enough to prove you talk cr@p.

For instance Cisco use 100MB when they refer to 100 Megabit switches,

Where did you see that Dennis?

snip



Just the first product I clicked on.

There is no standard for MB and Mb so anyone that wants to avoid
ambiguity spells it out.

Apart from SI (for the prefix) and IEEE 1541 (for the 'B' or 'b'). Stop
wriggling, dennis.




You can believe what you want but you will get it wrong.

On 07/04/2013 18:32, Bob Eager wrote:

There is no standard for MB and Mb so anyone that wants to avoid
ambiguity spells it out.

Apart from SI (for the prefix) and IEEE 1541 (for the 'B' or 'b'). Stop
wriggling, dennis.




BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

You can also tell me which standard is *the* standard

IEEE 1541
or
IEC 60027-2

which have different bits.

So go and wriggle yourself.

"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those types
of memory that use one (not most domestic machines, so far as I know).



--
Jeremy C B Nicoll - my opinions are my own.

Email sent to my from-address will be deleted. Instead, please reply
to replacing "aaa" by "284".

"Jeremy Nicoll - news posts" wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and
16 in a word (without the transport).

"bm" wrote:


"Jeremy Nicoll - news posts" wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and
16 in a word (without the transport).

Ah, right. Are there stop & start bits around every 8 bits of data?

There's also the overheads of TCP packets themselves, etc, in transmission.
I find that it's broadly accurate to divide any bps figure by 10 to get a
Bps one.

--
Jeremy C B Nicoll - my opinions are my own.

Email sent to my from-address will be deleted. Instead, please reply
to replacing "aaa" by "284".

"Jeremy Nicoll - news posts" wrote
in message nvalid...
"bm" wrote:


"Jeremy Nicoll - news posts" wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and
16 in a word (without the transport).

Ah, right. Are there stop & start bits around every 8 bits of data?

There's also the overheads of TCP packets themselves, etc, in
transmission.
I find that it's broadly accurate to divide any bps figure by 10 to get a
Bps one.

Ahhhhh, now, I have zero idea about TCP packet format but yea, I think 10 to
1 is broadly correct
With speeds these days, maybe they send say10 bytes with only one pair of
start/stop bits, no idea. Course, to fetch the byte before shunting it out
takes a finite time so maybe you need individual start/stops to allow time
for the fetch, dunno. Maybe Dennis can enlighten us.

On Mon, 8 Apr 2013 00:34:34 +0100, Jeremy Nicoll - news posts wrote:

Ah, right. Are there stop & start bits around every 8 bits of data?

Depends on the type of transmission. You can have zero or one start bit,
zero, one, one and half or two stop bits. Oh and a parity bit or not.

--
Cheers
Dave.

On 08/04/13 00:09, Jeremy Nicoll - news posts wrote:
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.
Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those types
of memory that use one (not most domestic machines, so far as I know).



a BYTE is always 8 bits by definition. parity bits and other protocol
overheads so on are not part of the byte.


--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On 08/04/13 00:20, bm wrote:
"Jeremy Nicoll - news posts" wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.
Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).
I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and
16 in a word (without the transport).
be careful with 'word' because I've seen 32 bit and 64 bit 'words'
bandied around.




--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On Mon, 08 Apr 2013 00:52:33 +0100, The Natural Philosopher wrote:

On 08/04/13 00:20, bm wrote:
"Jeremy Nicoll - news posts"
wrote in message
nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.
Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types of memory that use one (not most domestic machines, so far as I
know).
I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits'
(transmitted) that he wants but he'll find there are 8 bits in a byte,
4 in a nibble and 16 in a word (without the transport).
be careful with 'word' because I've seen 32 bit and 64 bit 'words'
bandied around.



I have a machine with a 12 bit word. And started programming on one with
24 bit words.

But dennis is trying to deflect his original error and wriggling again.
He maintains that there is no standard that says B means byte and b means
bit. There is. I pointed it out. He tried to change the subject. As usual.



--
Use the BIG mirror service in the UK: http://www.mirrorservice.org
My posts (including this one) are my copyright and if @diy_forums on
Twitter wish to tweet them they can pay me £30 a post
*lightning surge protection* - a w_tom conductor

On 08/04/13 00:34, Jeremy Nicoll - news posts wrote:
"bm" wrote:

"Jeremy Nicoll - news posts" wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.
Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).
I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and
16 in a word (without the transport).
Ah, right. Are there stop & start bits around every 8 bits of data?

There's also the overheads of TCP packets themselves, etc, in transmission.
I find that it's broadly accurate to divide any bps figure by 10 to get a
Bps one.


well you can't even say that. Ive seen 120kbyte/sec+ over a 100Mbps
ethernet link..at ethernet levels, Wiki says 97% of raw data rate in
terms of payload is possible.

https://en.wikipedia.org/wiki/Ethernet_frame

IP itself has a 20-24byte header and may carry several THOUSAND bytes of
payload.

I've seen that well over 95% on an uncongested megastream link.

10% overhead bitrate loss from your BRAS is perhaps a rule of thumb for
a broadband link, but even that is variable.

e.g. I get 377 upload on a 488 link a mere 77% of theoretical maximum

But I am currently getting 5282 net download, which if I applied 77%
to, would imply a synch speed of 6890!

I am synching at 6624 and I doubt my BRAS is over 6000. More like 5500.
which would be 96% 'efficiency'.

so rules of thumb are bloody rough when you get to the nitty gritty.




--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On 08/04/13 00:44, bm wrote:
Maybe Dennis can enlighten us.
Don't hold your breath.

--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On 08/04/13 00:58, Bob Eager wrote:
On Mon, 08 Apr 2013 00:52:33 +0100, The Natural Philosopher wrote:

On 08/04/13 00:20, bm wrote:
"Jeremy Nicoll - news posts"
wrote in message
nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.
Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types of memory that use one (not most domestic machines, so far as I
know).
I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits'
(transmitted) that he wants but he'll find there are 8 bits in a byte,
4 in a nibble and 16 in a word (without the transport).
be careful with 'word' because I've seen 32 bit and 64 bit 'words'
bandied around.


I have a machine with a 12 bit word. And started programming on one with
24 bit words.

But dennis is trying to deflect his original error and wriggling again.
He maintains that there is no standard that says B means byte and b means
bit. There is. I pointed it out. He tried to change the subject. As usual.



well we know that, but its an interesting topic and no one has failed to
notice that dennis is talking out if his bottom again.



--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On 07/04/2013 16:44, dennis@home wrote:
On 06/04/2013 23:37, bm wrote:
"dennis@home" wrote in message
eb.com...
On 06/04/2013 13:05, Steve Firth wrote:
"dennis@home" wrote:
[snip]

In professional circles serial links are always measured in bits per
second. Mb/s and MB/s are the same.

Horse****.

There are people that try to insist that Mb/s and MB/s are different.

Yes, people who know what they are talking about. Clearly this group
excludes you.

In reality professionals now write bits/s or bytes/s so there is no
misunderstanding.

How would you know what professionals do Pennis?



Well its easy enough to prove you talk cr@p.

For instance Cisco use 100MB when they refer to 100 Megabit switches,

Where did you see that Dennis?

snip



Just the first product I clicked on.

There is no standard for MB and Mb so anyone that wants to avoid
ambiguity spells it out.

Well I have observed B being used for byte, and b for bit pretty much
universally... so I am content to accept it as a defacto standard even
if there is no formal definition.

(You are the first I have seen suggest otherwise). There tends to be
more discrepancy on the interpretation of the SI prefixes and whether
they should by default be the powers of two versions or not, and hence
the MB and MiB or KB Vs KiB discussions etc.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Monday 08 April 2013 00:44 bm wrote in uk.d-i-y:


"Jeremy Nicoll - news posts" wrote
in message nvalid...
"bm" wrote:


"Jeremy Nicoll - news posts"
wrote in message
k.invalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble
and 16 in a word (without the transport).

Ah, right. Are there stop & start bits around every 8 bits of data?

There's also the overheads of TCP packets themselves, etc, in
transmission.
I find that it's broadly accurate to divide any bps figure by 10 to get a
Bps one.

Ahhhhh, now, I have zero idea about TCP packet format but yea, I think 10
to 1 is broadly correct
With speeds these days, maybe they send say10 bytes with only one pair of
start/stop bits, no idea. Course, to fetch the byte before shunting it out
takes a finite time so maybe you need individual start/stops to allow time
for the fetch, dunno. Maybe Dennis can enlighten us.

There are (roughly):

42 octets (8 bit blocks) of overhead in an ethernet packet, including
interframe gaps;

16 octets in the IPv4 packet

16 or more octets in the TCP header.

Those do not always add up (eg the IP packet may get fragmented) but it
gives an idea who much overhead there is when on typical ethernet, you can
only push 1500 octets in one ethernet frame (gigabit allows more, if
everyone agrees).

I've always worked on the "10 bit" conversion estimate too - often a good
enough rule of thumb.


--
Tim Watts Personal Blog: http://squiddy.blog.dionic.net/

http://www.sensorly.com/ Crowd mapping of 2G/3G/4G mobile signal coverage

Reading this on the web? See:
http://wiki.diyfaq.org.uk/index.php?title=Usenet

On 08/04/2013 00:44, bm wrote:
Ahhhhh, now, I have zero idea about TCP packet format but yea, I think 10 to
1 is broadly correct
With speeds these days, maybe they send say10 bytes with only one pair of
start/stop bits, no idea. Course, to fetch the byte before shunting it out
takes a finite time so maybe you need individual start/stops to allow time
for the fetch, dunno. Maybe Dennis can enlighten us.

There are no start or stop bits in synchronous communications protocols,
as used in anything better than a dial-up modem. There are other
protocol overheads which mean a rule of thumb is that a 10Mbit line will
transfer about 1MByte per second.

Andy

On 08/04/2013 01:09, The Natural Philosopher wrote:
well you can't even say that. Ive seen 120kbyte/sec+ over a 100Mbps
ethernet link..at ethernet levels, Wiki says 97% of raw data rate in
terms of payload is possible.

I can't say I've seen that much - ever. The advantage of the 10% rule is
easy arithmetic

Andy

On 08/04/13 09:07, Tim Streater wrote:
In article ,
Tim Watts wrote:

On Monday 08 April 2013 00:44 bm wrote in uk.d-i-y:

"Jeremy Nicoll - news posts"
wrote
in message nvalid...
"bm" wrote:


"Jeremy Nicoll - news posts"
wrote in message
k.invalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for
those
types
of memory that use one (not most domestic machines, so far as I
know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits'
(transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a
nibble
and 16 in a word (without the transport).

Ah, right. Are there stop & start bits around every 8 bits of data?

There's also the overheads of TCP packets themselves, etc, in
transmission.
I find that it's broadly accurate to divide any bps figure by 10
to get a
Bps one.
Ahhhhh, now, I have zero idea about TCP packet format but yea, I
think 10
to 1 is broadly correct
With speeds these days, maybe they send say10 bytes with only one
pair of
start/stop bits, no idea. Course, to fetch the byte before shunting
it out
takes a finite time so maybe you need individual start/stops to
allow time
for the fetch, dunno. Maybe Dennis can enlighten us.

Ethernet packets don't use start/stop bits.

well they have a synching preamble. which amounts to start bits


--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On 08/04/2013 10:35, The Natural Philosopher wrote:
On 08/04/13 09:07, Tim Streater wrote:
In article ,
Tim Watts wrote:

On Monday 08 April 2013 00:44 bm wrote in uk.d-i-y:

"Jeremy Nicoll - news posts"
wrote
in message nvalid...
"bm" wrote:


"Jeremy Nicoll - news posts"
wrote in message
k.invalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for
those
types
of memory that use one (not most domestic machines, so far as I
know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits'
(transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a
nibble
and 16 in a word (without the transport).

Ah, right. Are there stop & start bits around every 8 bits of data?

There's also the overheads of TCP packets themselves, etc, in
transmission.
I find that it's broadly accurate to divide any bps figure by 10
to get a
Bps one.
Ahhhhh, now, I have zero idea about TCP packet format but yea, I
think 10
to 1 is broadly correct
With speeds these days, maybe they send say10 bytes with only one
pair of
start/stop bits, no idea. Course, to fetch the byte before shunting
it out
takes a finite time so maybe you need individual start/stops to
allow time
for the fetch, dunno. Maybe Dennis can enlighten us.

Ethernet packets don't use start/stop bits.

well they have a synching preamble. which amounts to start bits


But all anyone really cares about is "I have two boxes - how fast can my
data get from box A to box B". How much overhead is added by protocol,
how many re-sends, how many bits are required to carry that data, all
are utterly irrelevant to the end user. Indeed, most of the time they
don't care about actual speed at all - only "If I want a file moved from
A to B, will I notice the time it takes, and if so, about how long?"
With a user hat on, that is all I care about.

--
Rod

On 08/04/2013 00:20, bm wrote:
"Jeremy Nicoll - news posts" wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and
16 in a word (without the transport).



No, modems are measured in baud which is symbols per second not bits per
second. A symbol can contain many bits.
Its how you can get gigabit Ethernet down a cable that can only manage
125MHz signals, you send symbols down two of the pairs and each symbol
can carry 10 data bits IIRC.

A byte isn't eight bits.
An octet is 8 bits.
A byte is just a group of adjacent bits that may or may not have eight
of them.
Just because its a popular misconception doesn't mean its correct, it
just means you have to allow for the misinformed getting it wrong.
It doesn't really matter to 99.9% of people but it sure does if you are
designing kit that has to interoperate with other kit.

Of course the famous and rather expensive error was what does m mean,
metres or miles and just how much can you miss Mars by?

BTW a word isn't 16 bits either, its whatever width the computer was
designed to use. Popular word sizes have been 14 bits, 32 bits, 24 bits
and a few others.

On 08/04/2013 00:44, bm wrote:
"Jeremy Nicoll - news posts" wrote
in message nvalid...
"bm" wrote:


"Jeremy Nicoll - news posts" wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and
16 in a word (without the transport).

Ah, right. Are there stop & start bits around every 8 bits of data?

There's also the overheads of TCP packets themselves, etc, in
transmission.
I find that it's broadly accurate to divide any bps figure by 10 to get a
Bps one.

Ahhhhh, now, I have zero idea about TCP packet format but yea, I think 10 to
1 is broadly correct
With speeds these days, maybe they send say10 bytes with only one pair of
start/stop bits, no idea. Course, to fetch the byte before shunting it out
takes a finite time so maybe you need individual start/stops to allow time
for the fetch, dunno. Maybe Dennis can enlighten us.



Enlighten yourself
http://en.wikipedia.org/wiki/Transmi...ntrol_Protocol

But don't forget to add the rest of the frame(s) around the TCP part
depending on what physical media you are sending it over.

If you are sending small data packets like chat then it could be 100:1
protocol to data.

On 08/04/2013 00:58, Bob Eager wrote:
On Mon, 08 Apr 2013 00:52:33 +0100, The Natural Philosopher wrote:

On 08/04/13 00:20, bm wrote:
"Jeremy Nicoll - news posts"
wrote in message
nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.
Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types of memory that use one (not most domestic machines, so far as I
know).
I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits'
(transmitted) that he wants but he'll find there are 8 bits in a byte,
4 in a nibble and 16 in a word (without the transport).
be careful with 'word' because I've seen 32 bit and 64 bit 'words'
bandied around.



I have a machine with a 12 bit word. And started programming on one with
24 bit words.

But dennis is trying to deflect his original error and wriggling again.
He maintains that there is no standard that says B means byte and b means
bit. There is. I pointed it out. He tried to change the subject. As usual.




If pointing out that your standard doesn't agree with a different
standard then I wriggled, however IMNSHO its you that is wriggling by
claiming I have changed the subject when I clearly just told you you are
wrong!

Anything else to do with size of bytes etc. has been introduced by other
people not by me. However I am prepared to point out the errors just as
I have yours.

On 08/04/2013 00:51, The Natural Philosopher wrote:
On 08/04/13 00:09, Jeremy Nicoll - news posts wrote:
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.
Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).



a BYTE is always 8 bits by definition. parity bits and other protocol
overheads so on are not part of the byte.



No it isn't.
Show your definition.

On 08/04/2013 11:17, dennis@home wrote:


A byte isn't eight bits.
An octet is 8 bits.
A byte is just a group of adjacent bits that may or may not have eight
of them.
Just because its a popular misconception doesn't mean its correct, it
just means you have to allow for the misinformed getting it wrong.
It doesn't really matter to 99.9% of people but it sure does if you are
designing kit that has to interoperate with other kit.

Of course the famous and rather expensive error was what does m mean,
metres or miles and just how much can you miss Mars by?

BTW a word isn't 16 bits either, its whatever width the computer was
designed to use. Popular word sizes have been 14 bits, 32 bits, 24 bits
and a few others.

If you today used the term 'byte' for anything other than eight bits,
you'd have to have a positively perverse aim of causing confusion.

Wiki suggests "The size of the byte has historically been hardware
dependent and no definitive standards existed that mandated the size.
The de facto standard of eight bits is a convenient power of two
permitting the values 0 through 255 for one byte. With ISO/IEC 80000-13,
this common meaning was codified in a formal standard."

As usual, the flaming standard seems not to be accessible. But willing
to believe Wiki on this matter.

If you ever use 'byte' to mean anything other than eight bits, it is up
to you as author to state that and explain. An unadorned, unexplained
'byte' simply IS eight bits.

--
Rod

On 08/04/2013 01:46, John Rumm wrote:
8

There is no standard for MB and Mb so anyone that wants to avoid
ambiguity spells it out.

Well I have observed B being used for byte, and b for bit pretty much
universally... so I am content to accept it as a defacto standard even
if there is no formal definition.

(You are the first I have seen suggest otherwise). There tends to be
more discrepancy on the interpretation of the SI prefixes and whether
they should by default be the powers of two versions or not, and hence
the MB and MiB or KB Vs KiB discussions etc.




Well like I pointed out even Cisco are inconsistent and use B for bit on
some products so you can assume what you want but don't rely on it for
anything important unless you understand the consequences.


The use of K/M and Ki/Mi is just trying to make it worse IMO.
Its fairly obvious that quoting disk/stick sizes in decimal millions is
just a marketing scam, as is quoting unformatted sizes.

On 08/04/2013 11:50, dennis@home wrote:


The use of K/M and Ki/Mi is just trying to make it worse IMO.
Its fairly obvious that quoting disk/stick sizes in decimal millions is
just a marketing scam, as is quoting unformatted sizes.

I still think that a better approach would have been something like
Ksubscript 2 or Ksubscript 10) when people were being specific -
otherwise it is assumed to be approximate and really doesn't matter
whether it is binary or decimal based.

--
Rod

On 08/04/2013 00:51, The Natural Philosopher wrote:
On 08/04/13 00:09, Jeremy Nicoll - news posts wrote:
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

a BYTE is always 8 bits by definition. parity bits and other protocol
overheads so on are not part of the byte.

Much as I hate to agree with dumb Dennis he does have a point here.

The C standard only requires that a byte must be able to represent *at
least* 256 distinct values it doesn't specify a bit length and some
implementations on 36bit machine architectures did use 9bit bytes.

Byte has come to mean 8bits in common parlance, but way back when memory
was really expensive and made of wires with toroidal cores or storage
tubes there were computers made with as few as 6 bits per byte.

The IBM701 for instance has 36 bit words and 18bit short integers and 6
bit bytes for characters as did several of its later derivatives.

http://en.wikipedia.org/wiki/Six-bit_character_code

Somewhere along the line having 32bits in a big iron machine word became
the norm and then 8 bits for characters sat nicely with BCD arithmetic.
There were two commonly used mutually incompatible machine
representations of alphanumeric text even more recently than that. ASCII
eventually won out in all but a handful of applications but I expect
EBCDIC lingers on like a bad smell in legacy banking code.

The notable near supercomputer CDC7600 was among the last of the breed
of mainframes to have an unconventional machine word length of 60bits.

--
Regards,
Martin Brown

On 08/04/2013 11:36, polygonum wrote:
On 08/04/2013 11:17, dennis@home wrote:


A byte isn't eight bits.
An octet is 8 bits.
A byte is just a group of adjacent bits that may or may not have eight
of them.
Just because its a popular misconception doesn't mean its correct, it
just means you have to allow for the misinformed getting it wrong.
It doesn't really matter to 99.9% of people but it sure does if you are
designing kit that has to interoperate with other kit.

Of course the famous and rather expensive error was what does m mean,
metres or miles and just how much can you miss Mars by?

BTW a word isn't 16 bits either, its whatever width the computer was
designed to use. Popular word sizes have been 14 bits, 32 bits, 24 bits
and a few others.

If you today used the term 'byte' for anything other than eight bits,
you'd have to have a positively perverse aim of causing confusion.

Wiki suggests "The size of the byte has historically been hardware
dependent and no definitive standards existed that mandated the size.
The de facto standard of eight bits is a convenient power of two
permitting the values 0 through 255 for one byte. With ISO/IEC 80000-13,
this common meaning was codified in a formal standard."

As usual, the flaming standard seems not to be accessible. But willing
to believe Wiki on this matter.

If you ever use 'byte' to mean anything other than eight bits, it is up
to you as author to state that and explain. An unadorned, unexplained
'byte' simply IS eight bits.


Well I did say a professional wouldn't use those terms and a
professional might well be involved in designing hardware not just some
casual computer user of software pleb who has no understanding of the
hardware anyway.

But there you are a bytes is not defined as 8 bits, it may be frequently
used to refer to 8 bits, it doesn't make it correct.

"dennis@home" wrote in message
.com...
On 08/04/2013 00:20, bm wrote:
"Jeremy Nicoll - news posts"
wrote
in message nvalid...
"dennis@home" wrote:

BTW maybe you can explain how many bits there are in a byte,
I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?

It'll also depend on whether you're counting the parity bit, for those
types
of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own
software UART he could have pretty much however many 'bits' (transmitted)
that he wants but he'll find there are 8 bits in a byte, 4 in a nibble
and
16 in a word (without the transport).



No, modems are measured in baud which is symbols per second not bits per
second. A symbol can contain many bits.

Well blow me down, for 40+ years i've understood baud-rate to be bits per
second, what a dummy.

snip

On 08/04/2013 12:08, dennis@home wrote:

But there you are a bytes is not defined as 8 bits, it may be frequently
used to refer to 8 bits, it doesn't make it correct.

WHich part of this did you have difficulty in understanding:

"With ISO/IEC 80000-13, this common meaning was codified in a formal
standard."

--
Rod

On Mon, 08 Apr 2013 01:09:55 +0100, The Natural Philosopher wrote:

But I am currently getting 5282 net download, which if I applied 77%
to, would imply a synch speed of 6890!

I am synching at 6624 and I doubt my BRAS is over 6000. More like 5500.
which would be 96% 'efficiency'.

BRAS is set in 512 kbps steps from 1 Mbps or there abouts up. Or was I'm
not sure they still do that.

http://www.kitz.co.uk/adsl/IPprofile.htm

Depends on the service you have.

--
Cheers
Dave.

On Mon, 08 Apr 2013 12:03:40 +0100, polygonum wrote:

The use of K/M and Ki/Mi is just trying to make it worse IMO.

I still think that a better approach would have been something like
Ksubscript 2 or Ksubscript 10) when people were being specific -

Why K? The SI prefix for a multiplier near 1000 is k.

As with bits and bytes (b/B). Why not k and K (1000/1024)?

I guess as a great many people don't seem able to grasp the significance
of the case of the prefixes that isn't a good idea. M or m?


--
Cheers
Dave.

On Monday, April 8, 2013 12:52:33 AM UTC+1, The Natural Philosopher wrote:
On 08/04/13 00:20, bm wrote:

"Jeremy Nicoll - news posts" wrote

in message nvalid...

"dennis@home" wrote:



BTW maybe you can explain how many bits there are in a byte,

I will give you a hint it isn't eight.

Depends on the machine architecture, doesn't it?



It'll also depend on whether you're counting the parity bit, for those

types

of memory that use one (not most domestic machines, so far as I know).

I think Dennis is including the start/stop bits. If he wrote his own

software UART he could have pretty much however many 'bits' (transmitted)

that he wants but he'll find there are 8 bits in a byte, 4 in a nibble and

16 in a word (without the transport).

be careful with 'word' because I've seen 32 bit and 64 bit 'words'

bandied around.

I'm sure I also remember long words too.











--

Ineptocracy



(in-ep-toc’-ra-cy) – a system of government where the least capable to lead are elected by the least capable of producing, and where the members of society least likely to sustain themselves or succeed, are rewarded with goods and services paid for by the confiscated wealth of a diminishing number of producers.

On 08/04/2013 11:17, dennis@home wrote:
A byte isn't eight bits.
An octet is 8 bits.
A byte is just a group of adjacent bits that may or may not have eight
of them.

I've worked on systems that didn't have 8 bit characters. We called the
6-bit units characters on one of them, and the other one didn't have an
equivalent concept - a word was 36-bits. (and a character in a file
could be sixbit or ascii)

In neither case did we call them bytes.

Andy

On 08/04/2013 12:10, bm wrote:
Well blow me down, for 40+ years i've understood baud-rate to be bits per
second, what a dummy.

you are far from alone.

Another example is a parallel bus such as SCSI or a printer bus which
sends whole characters in one go. The baud rate is the rate at which
each wire sends bits - but the data rate is 8 (or 16, or 32) times higher.

Andy