breadboarding fast, tiny stuff

[Joerg]

lha is a PC format, sit is a Mac and PC format and most tools open all
of them.

Then it may be ok but it sure will trigger a questions from clients like
"What's that?". Why do we need a myriad of formats when there is zip?

 

[Jeroen Belleman]

Then it may be ok but it sure will trigger a questions from clients like
"What's that?". Why do we need a myriad of formats when there is zip?

I think the real question is: Why do we need myriad formats when we
have tar? It probably predates them all. All those young whipper-
snappers keep re-inventing the wheel. Oh well.

Jeroen Belleman

(Now let's have some archive format history...)

 

[Joerg]

I think the real question is: Why do we need myriad formats when we
have tar? It probably predates them all. All those young whipper-
snappers keep re-inventing the wheel. Oh well.

Same reason as with video storage formats and such. Whatever wins in the
marketplace is going to be used in industry. And us consultants must use
what industry uses.

 

[Joel Koltner]

Same reason as with video storage formats and such. Whatever wins in the
marketplace is going to be used in industry. And us consultants must use
what industry uses.

"tar" also doesn't do any compression whatsoever -- it just packs everything
together into one file ("Tape ARchive"). The more contemporary *NIX file
format is .tgz ("tarred and then gZiped").

If you really want to go non-mainstream, formats such as .ace (WinAce) can
often gain an additional, say, 10% over Zip.

---Joel

 

[John Larkin]

"tar" also doesn't do any compression whatsoever -- it just packs everything
together into one file ("Tape ARchive"). The more contemporary *NIX file
format is .tgz ("tarred and then gZiped").

If you really want to go non-mainstream, formats such as .ace (WinAce) can
often gain an additional, say, 10% over Zip.

---Joel

Not to change the subject (horrors!) but I did a nice little
compression thing for Xilinx configuration streams. We build roms that
have uP application code and one or more fpga config data blocks, so
that the uP configures the fpga's at powerup. Sometimes the fpga
blocks get big, too big for, say, a 4 mbit eprom, so our rom builder
program compresses them and the uP decompresses at runtime. The
resulting rom space is 0.2 to 0.5 of the original size and bit-bangs
faster than the uncompressed version. The key here is that the config
data has long runs of zeroes.

One of the new Virtex parts has something like 80 megabits of config
space!

John

 

[Joel Koltner]

Sometimes the fpga
blocks get big, too big for, say, a 4 mbit eprom, so our rom builder
program compresses them and the uP decompresses at runtime...

I expect that sooner or later Xilinx will add decompression hardware to the
FPGAs themselves to take advantage of that (significant!) gain you're
seeing... they already have some versions that decrypt the bitstream, as I
recall, adding decompression to that seems pretty straightforward.

---Joel

 

[Joerg]

Not to change the subject (horrors!) but I did a nice little
compression thing for Xilinx configuration streams. We build roms that
have uP application code and one or more fpga config data blocks, so
that the uP configures the fpga's at powerup. Sometimes the fpga
blocks get big, too big for, say, a 4 mbit eprom, so our rom builder
program compresses them and the uP decompresses at runtime. The
resulting rom space is 0.2 to 0.5 of the original size and bit-bangs
faster than the uncompressed version. The key here is that the config
data has long runs of zeroes.

One of the new Virtex parts has something like 80 megabits of config
space!

Pretty soon kids will need 80M to do an LED blinker

 

[Joerg]

I expect that sooner or later Xilinx will add decompression hardware to the
FPGAs themselves to take advantage of that (significant!) gain you're
seeing... they already have some versions that decrypt the bitstream, as I
recall, adding decompression to that seems pretty straightforward.

"What time is it?"

"Wait, my wrist watch seems to have problems with the bootloader"

 

[John Larkin]

I expect that sooner or later Xilinx will add decompression hardware to the
FPGAs themselves to take advantage of that (significant!) gain you're
seeing... they already have some versions that decrypt the bitstream, as I
recall, adding decompression to that seems pretty straightforward.

---Joel

They already have a bitstream compression option that relies on
bitstream blocks being identical, so the can load the same data into
multiple clb's. In real life, that usually happens when they're all
zeroes, ie for unused hunks of chip. That saves 10-20% typically, but
it probably doesn't compound with my zeroes compression.

Some more elegant decompression would be cool. On the pc side, we
don't care if it would take another second or so to compress the
bitstream; hell, the Xilinx software should do it for us! They could
make the entire thing transparent.

The idea of an 80 megabit config stream gives me the creeps.

John

 

[Phil Hobbs]

"What time is it?"

"Wait, my wrist watch seems to have problems with the bootloader"

As it says in "The inmates are running the asylum",
"When you cross a microwave with a computer, what do you get?"
"A computer."
"When you cross a toaster with a computer, what do you get?"
"That's right, a computer."

I like analogue things.

Cheers,

Phil "self-winding mechanical watch" Hobbs

 

[Joerg]

As it says in "The inmates are running the asylum",
"When you cross a microwave with a computer, what do you get?"
"A computer."
"When you cross a toaster with a computer, what do you get?"
"That's right, a computer."

What do you get when that computer contains one of those cheap power
supplies? A toaster.

I like analogue things.

Me too!

Cheers,

Phil "self-winding mechanical watch" Hobbs

Ok, I've compromised but my watch still has hands. I don't look at a
cell phone when I need to check the time.

 

[John Larkin]

As it says in "The inmates are running the asylum",
"When you cross a microwave with a computer, what do you get?"
"A computer."
"When you cross a toaster with a computer, what do you get?"
"That's right, a computer."

I like analogue things.

Cheers,

Phil "self-winding mechanical watch" Hobbs

I've never owned a watch. I don't want some gadget strapped to my
wrist, telling me what to do when.

John

 

[Joel Koltner]

I've never owned a watch. I don't want some gadget strapped to my
wrist, telling me what to do when.

How do you know to go home at night, then?

I occasionally think that if you'd have grown up in California rather than
Mississippi, John, you might have been quite the surfer-dude.

 

[Michael A. Terrell]

Nasty! I have them safely inside my tube collection, wrapped in some foam
padding.

Just remember that if you drop them to dump ware on them, in case
they are cracked. If they aren't the water won't hurt them, but if it
is, it might save your life.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Michael A. Terrell]

As it says in "The inmates are running the asylum",
"When you cross a microwave with a computer, what do you get?"
"A computer."
"When you cross a toaster with a computer, what do you get?"
"That's right, a computer."

I like analogue things.

Cheers,

Phil "self-winding mechanical watch" Hobbs

Dimbulb had one of those, but it was always run down.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Michael A. Terrell]

How do you know to go home at night, then?

I occasionally think that if you'd have grown up in California rather than
Mississippi, John, you might have been quite the surfer-dude.

The sun is coming up, of course! ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Spehro Pefhany]

I've never owned a watch. I don't want some gadget strapped to my
wrist, telling me what to do when.

John

How do you feel about wedding rings? ;-)
Best regards,
Spehro Pefhany

 

[John Larkin]

How do you know to go home at night, then?

In my Volkswagen.

I occasionally think that if you'd have grown up in California rather than
Mississippi, John, you might have been quite the surfer-dude.

It was New Orleans, "the city that time forgot."

John

 

[Joel Koltner]

It was New Orleans, "the city that time forgot."

Sorry, I knew that, I was apparently thinking "Mississippi delta."

 

[JosephKK]

I've never owned a watch. I don't want some gadget strapped to my
wrist, telling me what to do when.

John

One of your watches (or an associate's) has been allowed to have too
much power. My provides current time only when I want to know. It
does not control my life.