WTB: Heathkit ID-4801 EPROM Programmer

[David Brown]

On 26/10/2010 23:51, Joe Pfeiffer wrote:

Ahem A Rivet's Shot<steveo@eircom.net> writes:

On Tue, 26 Oct 2010 19:19:29 +0200
"F. Bertolazzi"<TOGLIeset@MAIUSCOLEtdd.it> wrote:

Ahem A Rivet's Shot:

These days you could probably add a set of ports to a PC, wire
them to a DIP plug and emulate the EPROM in software complete with the
timing characteristics.

I definitely don't think so. A PC must handle lots of unpredictable
interrupts that will skew the timings.

They can all be turned off.

Rubbish, unless you are doing bare-metal programming on the PC (and no
sane person would do that).

On the other hand, using a parallel
FTDI chip...

Sure that'll work.

No, it will not work - USB 1.1 (as used by most FTDI chips) runs on a 1
ms cycle. Even with USB 2.0 (as used by some faster FTDI chips) runs on
a 0.1 ms cycle. This means that any time you need to read a port then
set some outputs based on the inputs, you have an absolute minimum of
0.2 ms latency - three orders of magnitude too high for an eprom
emulator. For proper emulation of the signal sequencing, you would need
several read-write cycles making it even worse.

This is definitely a project where the right way to do it would be to
have a little PIC managing low-level timing, and talking to the PC over
USB.

That's almost right - but drop the "PIC". They are horrible devices,
and too slow here. Even using a decent small micro like an AVR, you
couldn't emulate an eeprom at more than about 1-2 MHz. And if you have
a chip that is fast enough, it is difficult to get consistent timings.

A much better idea is to use a small programmable logic device with a
ram chip and a USB connection. You don't need much - a 128 macrocell
PLD would be enough if you use an FTDI chip for the usb connection. Or
you could buy one of FTDI's modules with a Cylone FPGA - it's overkill,
but easily available and ready-made.

 

[Ahem A Rivet's Shot]

On Wed, 27 Oct 2010 11:33:59 +0200
David Brown <david@westcontrol.removethisbit.com> wrote:

On 26/10/2010 23:51, Joe Pfeiffer wrote:
Ahem A Rivet's Shot<steveo@eircom.net> writes:

On Tue, 26 Oct 2010 19:19:29 +0200
"F. Bertolazzi"<TOGLIeset@MAIUSCOLEtdd.it> wrote:

Ahem A Rivet's Shot:

These days you could probably add a set of ports to a PC,
wire them to a DIP plug and emulate the EPROM in software complete
with the timing characteristics.

I definitely don't think so. A PC must handle lots of unpredictable
interrupts that will skew the timings.

They can all be turned off.


Rubbish, unless you are doing bare-metal programming on the PC (and no
sane person would do that).

Which if you look elsethread you will see is exactly what I had in
mind - I never suggested this was a sane thing to do (quite the opposite),
just that it was probably possible.

--
Steve O'Hara-Smith | Directable Mirror Arrays
C:>WIN | A better way to focus the sun
The computer obeys and wins. | licences available see
You lose and Bill collects. | http://www.sohara.org/

 

[Joe Pfeiffer]

"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:

Joe Pfeiffer:

Their instruction set is certainly weird, but their processors are so
perfectly suited to tasks like this...

Have you ever taken a look at Atmel's AVRs?
Since I did, no more PICs.

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....
--
As we enjoy great advantages from the inventions of others, we should
be glad of an opportunity to serve others by any invention of ours;
and this we should do freely and generously. (Benjamin Franklin)

 

[F. Bertolazzi]

Joe Pfeiffer:

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....

I did because, at the time, were the best ones in their class.
But with AVRs it's a completely different life, both in assembly and in C.

--
Saluti

 

[Joe Pfeiffer]

"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:

Joe Pfeiffer:

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....

I did because, at the time, were the best ones in their class.
But with AVRs it's a completely different life, both in assembly and in C.

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.
--
As we enjoy great advantages from the inventions of others, we should
be glad of an opportunity to serve others by any invention of ours;
and this we should do freely and generously. (Benjamin Franklin)

 

[F. Bertolazzi]

Joe Pfeiffer:

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.

It uses one more pin, but I guess that uses the same connector (3x2 pin
header), unless Microchip did the not very smart mofe of using a 5x1.

Or three less, since the new Debugwire, that can inspect the internal
registers and memories by using just he reset pin & GND, can also program
the Flash (but not the configuration fuses).

On top of that most AVRs have all the hardware required for bootloader
implementation.

 

[F. Bertolazzi]

Charlie Gibbs:

To me it looks like some newfangled trademark, say for a Viagra-like
drug.

"Noplis, I have a headache."

LOL. It actually come from a joke about a safari.

The participants bragged about how many lions, gazelles etc. they killed,
while one of them only got some Noplis.

- What are Noplis? - asked another hunter.
- Dunno, sort of apes that, when aimed at, scream "noplis, noplis".

 

[Charlie Gibbs]

In article <1bhbg8493a.fsf@snowball.wb.pfeifferfamily.net>,
pfeiffer@cs.nmsu.edu (Joe Pfeiffer) writes:

"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:

Joe Pfeiffer:

"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:

Joe Pfeiffer:

This is definitely a project where the right way to do it would
be to have a little PIC

Noplis.

Sorry? (I'm afraid I only read English)

"No, please".

I suppose it would sound lame to say that occurred to me, but I
figured it must have been a real word....

To me it looks like some newfangled trademark, say for a Viagra-like
drug.

"Noplis, I have a headache."

--
/~\ cgibbs@kltpzyxm.invalid (Charlie Gibbs)
\ / I'm really at ac.dekanfrus if you read it the right way.
X Top-posted messages will probably be ignored. See RFC1855.
/ \ HTML will DEFINITELY be ignored. Join the ASCII ribbon campaign!

 

[Grant Edwards]

On 2010-10-27, Joe Pfeiffer <pfeiffer@cs.nmsu.edu> wrote:

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header
strip) is really convenient.

Pretty much the same for AVR.

--
Grant Edwards grant.b.edwards Yow! Did an Italian CRANE
at OPERATOR just experience
gmail.com uninhibited sensations in
a MALIBU HOT TUB?

 

[Rich Grise]

On Wed, 27 Oct 2010 18:56:19 +0200, F. Bertolazzi wrote:

Charlie Gibbs:

To me it looks like some newfangled trademark, say for a Viagra-like
drug.

"Noplis, I have a headache."

LOL. It actually come from a joke about a safari.

The participants bragged about how many lions, gazelles etc. they killed,
while one of them only got some Noplis.

- What are Noplis? - asked another hunter.
- Dunno, sort of apes that, when aimed at, scream "noplis, noplis".

"Don't step in the huzzanga!"

;-)
Rich

 

[Rich Grise]

On Wed, 27 Oct 2010 10:37:30 -0600, Joe Pfeiffer wrote:

"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:
Joe Pfeiffer:

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....

I did because, at the time, were the best ones in their class.
But with AVRs it's a completely different life, both in assembly and in C.

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.

But bank switching is Evil. ;-)

Cheers!
Rich

 

[Joe Pfeiffer]

"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:

Joe Pfeiffer:

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.

It uses one more pin, but I guess that uses the same connector (3x2 pin
header), unless Microchip did the not very smart mofe of using a 5x1.

They actually use 6x1 (with one of the six unused).

Or three less, since the new Debugwire, that can inspect the internal
registers and memories by using just he reset pin & GND, can also program
the Flash (but not the configuration fuses).

On top of that most AVRs have all the hardware required for bootloader
implementation.

--
As we enjoy great advantages from the inventions of others, we should
be glad of an opportunity to serve others by any invention of ours;
and this we should do freely and generously. (Benjamin Franklin)

 

[F. Bertolazzi]

Rich Grise:

"Don't step in the huzzanga!"

What's that? Tell me, tell me!

 

[Rich Grise]

On Wed, 27 Oct 2010 22:42:02 +0200, F. Bertolazzi wrote:

Rich Grise:

"Don't step in the huzzanga!"

What's that? Tell me, tell me!

Some missionary was speechifying in some village, and at every salient
point, the crowd would chant, "Huzzanga! Huzzanga!"

Of course, he assumed they were cheering hin on. (compare "Hooray!")

Well, after his speech, the chieftan takes him on a tour of the village,
and says, "Careful, don't step in the huzzanga!"

Cheers!
Rich

 

[Michael A. Terrell]

Rich Grise wrote:

On Wed, 27 Oct 2010 10:37:30 -0600, Joe Pfeiffer wrote:
"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:
Joe Pfeiffer:

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....

I did because, at the time, were the best ones in their class.
But with AVRs it's a completely different life, both in assembly and in C.

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.

But bank switching is Evil. ;-)

Not always. Some banks are evil, others are just incompetent.


--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

 

[F. Bertolazzi]

Rich Grise:

Some missionary was speechifying in some village, and at every salient
point, the crowd would chant, "Huzzanga! Huzzanga!"

Of course, he assumed they were cheering hin on. (compare "Hooray!")

Well, after his speech, the chieftan takes him on a tour of the village,
and says, "Careful, don't step in the huzzanga!"

Good! I was expecting the stuff "either huzzanga or else die".

 

[Rich Grise]

On Thu, 28 Oct 2010 02:30:04 +0200, F. Bertolazzi wrote:

Rich Grise:

Some missionary was speechifying in some village, and at every salient
point, the crowd would chant, "Huzzanga! Huzzanga!"

Of course, he assumed they were cheering hin on. (compare "Hooray!")

Well, after his speech, the chieftan takes him on a tour of the village,
and says, "Careful, don't step in the huzzanga!"

Good! I was expecting the stuff "either huzzanga or else die".

Nah, that's the Foo bird. ;-)

Cheers!
Rich

 

[Rich Grise]

On Wed, 27 Oct 2010 19:40:03 -0400, Michael A. Terrell wrote:

Rich Grise wrote:
On Wed, 27 Oct 2010 10:37:30 -0600, Joe Pfeiffer wrote:
"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:
Joe Pfeiffer:

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....

I did because, at the time, were the best ones in their class.
But with AVRs it's a completely different life, both in assembly and in C.

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.

But bank switching is Evil. ;-)

Not always. Some banks are evil, others are just incompetent.

Memory banks, you nincompoop.

Thanks,
Rich

 

[David Brown]

On 28/10/2010 07:47, Rich Grise wrote:

On Wed, 27 Oct 2010 19:40:03 -0400, Michael A. Terrell wrote:
Rich Grise wrote:
On Wed, 27 Oct 2010 10:37:30 -0600, Joe Pfeiffer wrote:
"F. Bertolazzi"<TOGLIeset@MAIUSCOLEtdd.it> writes:
Joe Pfeiffer:

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....

I did because, at the time, were the best ones in their class.
But with AVRs it's a completely different life, both in assembly and in C.

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.

But bank switching is Evil. ;-)

Not always. Some banks are evil, others are just incompetent.

Memory banks, you nincompoop.

On the PIC, the same thing applies to memory banks...

 

[Michael A. Terrell]

Rich Grise wrote:

On Wed, 27 Oct 2010 19:40:03 -0400, Michael A. Terrell wrote:
Rich Grise wrote:
On Wed, 27 Oct 2010 10:37:30 -0600, Joe Pfeiffer wrote:
"F. Bertolazzi" <TOGLIeset@MAIUSCOLEtdd.it> writes:
Joe Pfeiffer:

No, I haven't -- I don't quite remember why I wound up going down the
PIC path....

I did because, at the time, were the best ones in their class.
But with AVRs it's a completely different life, both in assembly and in C.

How is the AVR programmed? PIC's in-circuit programming (three pins
plus power and ground need to come to some standard male header strip)
is really convenient.

But bank switching is Evil. ;-)

Not always. Some banks are evil, others are just incompetent.

Memory banks, you nincompoop.

Look who's talking. I'll bet you hit the local food bank quite
often.


--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.