Elektor EPROM Emulator flaky - continued

J

Jack

Guest
(Response to Petrus Bitbyter in sci.eletronics):

Original message:

I constructed the EPROM Emulator published in Elektor magazine in the
SEPTEMBER 1992 issue. It worked quite well under Win98, but lately I
started using it on a HP Compaq nx9010 Pentium 4 laptop using WinXP,
and am getting inconsistent results. The downloading of code into the
target works successfully 1 out of 10 attempts. When the download
fails, the download LED flickers on and off. When the download was
successful, the LED stayed on continuously.

Any ideas? I tried changing the parallel port mode on the laptop to
Output Only, Bidirectional, EPP and ECP but no change.

Thanks

-------------------------------------------------------------------------------

Follow-up:

I might be referring to the wrong Elektor article - the article I
referred to is the one NOT using a Windows driver, i.e. I download my
object code using a DOS command line copy command in binary format
i.e.

copy <8051 object file> lpt1 /b

Regards
 
On 17 Sep 2004 06:03:35 -0700, jchirac33@hotmail.com (Jack) wrote:

(Response to Petrus Bitbyter in sci.eletronics):

Original message:

I constructed the EPROM Emulator published in Elektor magazine in the
SEPTEMBER 1992 issue. It worked quite well under Win98, but lately I
started using it on a HP Compaq nx9010 Pentium 4 laptop using WinXP,
and am getting inconsistent results. The downloading of code into the
target works successfully 1 out of 10 attempts. When the download
fails, the download LED flickers on and off. When the download was
successful, the LED stayed on continuously.

Any ideas? I tried changing the parallel port mode on the laptop to
Output Only, Bidirectional, EPP and ECP but no change.

Thanks

-------------------------------------------------------------------------------

Follow-up:

I might be referring to the wrong Elektor article - the article I
referred to is the one NOT using a Windows driver, i.e. I download my
object code using a DOS command line copy command in binary format
i.e.

copy <8051 object file> lpt1 /b

Regards
Click to expand...
I use a parallel port PIC programmer and had problems under XP with
the programming mode continually being reset (LED's flashing!). This
registry hack fixed it for me. It seems XP continually polls the
parallel port and this interferes with other uses.

[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Parport\Parameters]
"DisableWarmPoll"=dword:00000001

Please let me know if it cures your problem - I will add it to my list
of "known cures" :)

Rick.
 
"Captain Rick" <ME@127.0.0.1> wrote in message
news:r35ok05pvt92b8kk8a5ok83nks9rrqnpl5@4ax.com...
On 17 Sep 2004 06:03:35 -0700, jchirac33@hotmail.com (Jack) wrote:

(Response to Petrus Bitbyter in sci.eletronics):

Original message:

I constructed the EPROM Emulator published in Elektor magazine in the
SEPTEMBER 1992 issue. It worked quite well under Win98, but lately I
started using it on a HP Compaq nx9010 Pentium 4 laptop using WinXP,
and am getting inconsistent results. The downloading of code into the
target works successfully 1 out of 10 attempts. When the download
fails, the download LED flickers on and off. When the download was
successful, the LED stayed on continuously.

Any ideas? I tried changing the parallel port mode on the laptop to
Output Only, Bidirectional, EPP and ECP but no change.

Thanks


------------------------------------------------------------------------------
-

Follow-up:

I might be referring to the wrong Elektor article - the article I
referred to is the one NOT using a Windows driver, i.e. I download my
object code using a DOS command line copy command in binary format
i.e.

copy <8051 object file> lpt1 /b

Regards

I use a parallel port PIC programmer and had problems under XP with
the programming mode continually being reset (LED's flashing!). This
registry hack fixed it for me. It seems XP continually polls the
parallel port and this interferes with other uses.

[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Parport\Parameters]
"DisableWarmPoll"=dword:00000001

Please let me know if it cures your problem - I will add it to my list
of "known cures" :)

Rick.
Click to expand...

Gee, the differences in the OS are likely the problem. XP requires you to use
system calls to access any peripheral (port) and tries to guard against any
program accessing the Ports directly. Frankly I do not know how to correct
this. It is built into the OS.

I may be wrong. But this was the explanation I got when I tried to run a couple
of my older programs under XP. I run them in the DOS mode now and they work.
But I don't know anything about your download program, so your still short
enough information to solve your problem.
 
In message <r35ok05pvt92b8kk8a5ok83nks9rrqnpl5@4ax.com>, Captain Rick
<ME@127.0.0.1> writes
I use a parallel port PIC programmer and had problems under XP with
the programming mode continually being reset (LED's flashing!). This
registry hack fixed it for me. It seems XP continually polls the
parallel port and this interferes with other uses.

[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Parport\Parameters]
"DisableWarmPoll"=dword:00000001

Please let me know if it cures your problem - I will add it to my list
of "known cures" :)

Rick.
As an aside to this, are you aware that most Laptops and many desktop
Click to expand...
machines are only 3.3v parallel ports.... if the interface on the
Emulator isn't 3.3V compliant, it may also cause problems.
--
Clint Sharp
 
Clint Sharp <clint@clintsmc.demon.co.uk> wrote in message news:<$$IhmSDZ3YTBFwCo@clintsmc.demon.co.uk>...
In message <r35ok05pvt92b8kk8a5ok83nks9rrqnpl5@4ax.com>, Captain Rick
ME@127.0.0.1> writes
I use a parallel port PIC programmer and had problems under XP with
the programming mode continually being reset (LED's flashing!). This
registry hack fixed it for me. It seems XP continually polls the
parallel port and this interferes with other uses.

[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Parport\Parameters]
"DisableWarmPoll"=dword:00000001

Please let me know if it cures your problem - I will add it to my list
of "known cures" :)

Rick.
As an aside to this, are you aware that most Laptops and many desktop
machines are only 3.3v parallel ports.... if the interface on the
Emulator isn't 3.3V compliant, it may also cause problems.
Click to expand...
Thank you for all the useful responses, which I only managed to read
on Monday morning!

Over the past weekend, I probed the Centronics STROBE line going into
the emulator using an oscilloscope. Suddenly the code downloading
process was more reliable whilst the 'scope was connected! I replaced
the 'scope with a 10k resistor to ground and was able to download more
consistently.

I would suspect that the 7407 buffer on the strobe line might be
faulty, but I will first check out the registry setting issue as well
as the 3.3V issue. I will feed back results ASAP.

To Clarence - I am using the DOS command line binary copy to LPT1 to
load the object into the emulator.

Jack
 
jchirac33@hotmail.com (Jack) wrote in message news:<22848a91.0409192358.67ae0b63@posting.google.com>...
Clint Sharp <clint@clintsmc.demon.co.uk> wrote in message news:<$$IhmSDZ3YTBFwCo@clintsmc.demon.co.uk>...
In message <r35ok05pvt92b8kk8a5ok83nks9rrqnpl5@4ax.com>, Captain Rick
ME@127.0.0.1> writes
I use a parallel port PIC programmer and had problems under XP with
the programming mode continually being reset (LED's flashing!). This
registry hack fixed it for me. It seems XP continually polls the
parallel port and this interferes with other uses.

[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Parport\Parameters]
"DisableWarmPoll"=dword:00000001

Please let me know if it cures your problem - I will add it to my list
of "known cures" :)

Rick.
As an aside to this, are you aware that most Laptops and many desktop
machines are only 3.3v parallel ports.... if the interface on the
Emulator isn't 3.3V compliant, it may also cause problems.

Thank you for all the useful responses, which I only managed to read
on Monday morning!

Over the past weekend, I probed the Centronics STROBE line going into
the emulator using an oscilloscope. Suddenly the code downloading
process was more reliable whilst the 'scope was connected! I replaced
the 'scope with a 10k resistor to ground and was able to download more
consistently.

I would suspect that the 7407 buffer on the strobe line might be
faulty, but I will first check out the registry setting issue as well
as the 3.3V issue. I will feed back results ASAP.

To Clarence - I am using the DOS command line binary copy to LPT1 to
load the object into the emulator.

Jack
Click to expand...
Some feedback:
I tried the registry setting change, but this did not have any effect.
I checked the Centronics voltage levels from the laptop, and it seems
they are indeed 3.3V levels. However, the 7407 specs indicate minimum
high voltage of 2V, so it should be able to handle a STROBE line at
3.3V.
I will replace the 7407 (and maybe also try out a 74LS07).
Jack
 
I replaced the 7407 buffer with a 74LS07 buffer, but this did not have
any effect.

I guess I will now have to fall back to putting a high value resistor
between STROBE and ground (on the output side of the buffer) - this
seems to have worked last time I tried it...

Any other recommendations would be appreciated...

Jack
 
jchirac33@hotmail.com (Jack) wrote in message news:<22848a91.0409212316.5c861674@posting.google.com>...
I replaced the 7407 buffer with a 74LS07 buffer, but this did not have
any effect.

I guess I will now have to fall back to putting a high value resistor
between STROBE and ground (on the output side of the buffer) - this
seems to have worked last time I tried it...

Any other recommendations would be appreciated...

Jack
Click to expand...
I soldered a 10k resistor between the Centronics STROBE line (on
output of 74LS07 buffer) and ground, and now code images are being
downloaded into the emulator without problems.
 
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