mal auf Papier an. Das
soll ja auch schmal helfe.
Vielen Dank
Richard
Ursprüngliche Nachricht Von: Jan Kandziora
Datum:05.02.2017 21:12 (GMT+01:00) An:
"OWFS (One-wire file system) discussion and help"
Betreff: Re:
[Owfs-developers] DS2450 CRC16 Checksum calcu
Am 05.02.2017 um 18:12 schrieb Ritchie:
> Can you explain, how it work, that the result of the Checksume is
> always 0xB001, if it is good.
>
Was genau ist dein Problem damit? Ich kann dir das Testen deines
DS2450-Klons nicht abnehmen, meist sind es Kleinigkeiten, die einem
einen CRC versauen. Der
Can you explain, how it work, that the result of the Checksume is
always 0xB001, if it is good.
CRC16seeded
...
if (sd == 0xB001) {
ret = 0;/* good */
} else {
ret = -1; /* error */
Am 04.02.2017 um 20:42 schrieb Ritchie:
>
> Is this correct, that the checksum is started with the value of "address" ?
>
Please see module/owlib/src/c/ow_2450.c:392 -- OW_w_mem()
423: if ( CRC16seeded(buf, 3, offset + i) || (echo[0] != p[i]) ) {
So, it's indeed seeded with 8+1 == 9.
Kind re
Hi all,
I am trying to simulate a DS2450 and don't find the reason for the wrong
checksume calculation of the write command 0x55
A good data translation will show the following result:
2450 OW_w_mem Adr.: 8 data : 0
CRC16seeded 55 8 0 0 6f f1 CRC b001 == 0xB001 o.k.
CRC16seeded 8c 3e 5c CRC
Dnia 21.02.2012 o 21:40 ekgnkb3d ekgnkb3d
napisał(a):
>
> Just for your information:
> on maxim-ic.com is the quite popular quad ADC DS2450 was put on status
> NRND
> (see http://www.maxim-ic.com/datasheet/index.mvp/id/2921/t/or#f here )
> There is no replacement listet, it looks like it is
Just for your information:
on maxim-ic.com is the quite popular quad ADC DS2450 was put on status NRND
(see http://www.maxim-ic.com/datasheet/index.mvp/id/2921/t/or#f here )
There is no replacement listet, it looks like it is simply discontinued...
:-(
Maybe this have to do with the 1-wire paten
Hi all,
I have several pressure sensors connected to a DS2450 each. Now I'm
monitoring the measured pressure and sometimes I see pressure jumps.
Before each pressure jump, the sensor stucks and then jumps to a higher
value.
To ensure that it is not the sensor, which causes this trouble, I
sour
nice, is .all a internal owfs function or device based function?
2011/1/31 Paul Alfille :
> Jim Duda just wrote me to say the problem was in the external circuit.
>
> On Sun, Jan 30, 2011 at 8:04 PM, Roberto Spadim wrote:
>> i think they are acquired in different times, not?
>>
>> 2011/1/30 Jim D
Jim Duda just wrote me to say the problem was in the external circuit.
On Sun, Jan 30, 2011 at 8:04 PM, Roberto Spadim wrote:
> i think they are acquired in different times, not?
>
> 2011/1/30 Jim Duda :
>> Hello,
>>
>> Running owfs-2.8p6.
>>
>> I'm a little confused as to how to use the DS2450 t
i think they are acquired in different times, not?
2011/1/30 Jim Duda :
> Hello,
>
> Running owfs-2.8p6.
>
> I'm a little confused as to how to use the DS2450 to read voltages.
>
> I find that if I view the device via the HTTP browser interface, the voltages
> are not consistent.
> Each time I us
Le Tue, 11 Jan 2011 15:28:45 -0500
Paul Alfille a écrit:
> Are you trying to speed up data acquisition? Even though the DAC is
> set to 16 bit resolution now the hardware is really 8 bit. I could
> just adjust the code I'd no one minds.
Well, if it can speed up acquisition it's a good thing. :)
report here, to update current owfs version tree
2011/1/11 Roberto Spadim :
> i think so, i changed 18b20 last time, there´s some easy features like
> temperature9 - 9bits
> temperature10- 10bits
> temperature11- 11bits
>
> check source code, and try to make a new 'file'
>
>
> 2011/1/11 Paul Alfil
i think so, i changed 18b20 last time, there´s some easy features like
temperature9 - 9bits
temperature10- 10bits
temperature11- 11bits
check source code, and try to make a new 'file'
2011/1/11 Paul Alfille :
> Are you trying to speed up data acquisition? Even though the DAC is set to
> 16 bit r
Are you trying to speed up data acquisition? Even though the DAC is set to
16 bit resolution now the hardware is really 8 bit. I could just adjust the
code I'd no one minds.
O> Hello,
>
> I would like to be able to limit the ADC conversions to 8 bits, how can
> I do this with owfs? Do I have to mod
Hello,
I would like to be able to limit the ADC conversions to 8 bits, how can
I do this with owfs? Do I have to modify the ow_2450.c file in owlib?
Thank you.
--
Stéphane ACOUNIS
SUBATECH Nantes - Service d'Électronique
Tél: 02-51-85-84-28 06-64-62-99-20
«Faut pas se laisser abattre» devise
$ owread -s 3000 /28.2CCD8000/temperature
30
$
It is work.
--
Serg.
Original Message
Subject: Re: [Owfs-developers] DS2450 alarm thresholds
From: Jim Kusznir
To: OWFS (One-wire file system) discussion and help
Date: 26.02.2010 19:07
> Yea, we were doing that..
Yea, we were doing that...We could even read the new voltage and see
that it exceeded the alarm threshold, but it didn't alarm.
We were actually trying to do most of this through owperl. We had a
loop where we would do the simultaneous->convert about once a second,
but devices were pretty much al
Just note that it is not sufficient to poll alarm directory to discover
units with threshold voltages .
The alarm condition is only set after a conversion. You have to trigger this
conversion in you polling loop via a simultaneous command.
Pascal
2010/2/26 Alessio Sangalli
> On 02/25/2010 04:1
On 02/25/2010 04:15 PM, Paul Alfille wrote:
> When in alarm condition, the device should appear in the /alarm directory.
>
> OWFS won't automatically poll the device, you need to do this in your
> program. (It can be as simple as a shell script with a loop and a
> "sleep" command).
Oh ok this mak
We've attempted to do this for our own uses (somewhat similar).
Unfortunately, owfs appears to have bugs in this area and does not
perform correctly. I hope to have time to do some low-level debugging
with the 2450 datasheet to figure out where the problem is and submit
a specific bug report.
In
When in alarm condition, the device should appear in the /alarm directory.
OWFS won't automatically poll the device, you need to do this in your
program. (It can be as simple as a shell script with a loop and a "sleep"
command).
Paul Alfille
On Thu, Feb 25, 2010 at 6:40 PM, Alessio Sangalli wrot
Just a question: in what way I can use DS2450's alarm threshold feature?
Basically, I want to "monitor" and "detect" overvoltages coming on the
Vin. Say I want to "report" everytime the voltage goes above 20VDC (when
the nominal is 14VCD).
I could setup a voltage divider so that I can measure u
Allesio
After a conversion (measurement) is done, the raw data can be read from
memory (page 0).
This is a little less efficient since the memory page is read twice, once
for the voltage and once for the page. Still, data A/D is probably the
slowest part of the sequence.
The data sheet calls the
Paul Alfille wrote:
> It's certainly possible to give the raw byte sequence. There is a slight
> Are you using a platform where floating point arithmetic is
> inconvenient? I'm told the true resolution is only 8 bit even though
> 16bit is set, so rounding errors are probably irrelevant.
Well I do
It's certainly possible to give the raw byte sequence. There is a slight
wrinkle that the DS2450 does A/D conversion either 0-2.5V or 0-5V and we use
the requested property to transparently set the correct resolution.
>From modules/owlib/src/c/ow_2450.c:
// data conversions
f[0] = (resolu
Hi, I am using a DS2450 to control voltages.
I use a voltage divider, 33K + 10K resistors and measure the voltage in
the middle to measure up to about 20V.
I have to calibrate each ADC to get an accurate reading depending on the
real value of the resistors.
In this operation I would be more comf
Am Freitag, 23. November 2007 13:48 schrieb Rob Conway:
>
> Isolated is probably the wrong word, as the neg of all inputs is tied to
> the neg of the 1wire supply.
>
No, I really asked about the ground potential. If there is a connector between
the DS2450 GND pin and the input's GND, it's likely t
Jan,
Isolated is probably the wrong word, as the neg of all inputs is tied to the
neg of the 1wire supply.
- Original Message -
From: "Jan Kandziora" <[EMAIL PROTECTED]>
To:
Sent: Friday, November 23, 2007 11:38 PM
Subject: Re: [Owfs-developers] DS2450 A/D has offset
Am Freitag, 23. November 2007 11:28 schrieb Rob Conway:
> Just wondering if anybody else has used the DS2450 for a long time. I am
> using one of these A/D's and I have found that after a while ~6-8 months
> all channels have a ~0.3 volt offset from zero. ie all 4 channel readings
> go up by ~.3
Just wondering if anybody else has used the DS2450 for a long time. I am using
one of these A/D's and I have found that after a while ~6-8 months all channels
have a ~0.3 volt offset from zero. ie all 4 channel readings go up by ~.3
volts. Its like the chips internal reference voltage somehow
, I
put in support.
Paul Alfille
-Original Message-
From: [EMAIL PROTECTED] on behalf of Roberto Spadim
Sent: Tue 9/26/2006 4:32 PM
To: owfs-developers@lists.sourceforge.net
Subject: [Owfs-developers] DS2450
Hello guys i was buying ds2405 for input and output, today i bought an
ds2450 for t
hello
i put 2450 on the bus, sometimes it appear sometime not :( i could only
read the volts one time :(
i could get device id
http://172.16.0.1:90/20.EF3D0300
what could i do to know were is the problem?
-
Tak
hello
i put 2450 on the bus, sometimes it appear sometime not :( i could only
read the volts one time :(
i could get device id
http://172.16.0.1:90/20.EF3D0300
what could i do to know were is the problem?
-
Take Survey
Am Mittwoch, 27. September 2006 05:30 schrieb Roberto Spadim:
> ok now i readed datasheet fully...
>
>
> In the shaded areas (8 to 16 bits area) the accuracy is less than the
> resolution. The conversion results may include random
> noise.
>
> ok, so i can understood that it have 8 bit acurracy and
minimum full scale input voltage (V)???
with diferent resolution i need diferent range???
i didn't understood page 22 can anyone help me? :)
Roberto Spadim escreveu:
> does DS2450 an 16bit ad??? or just 16bit ad with 0-5 range? and 8bit
> with 0-2.5 range?
> i didn't understand, cause in datashe
ok now i readed datasheet fully...
In the shaded areas (8 to 16 bits area) the accuracy is less than the
resolution. The conversion results may include random
noise.
ok, so i can understood that it have 8 bit acurracy and 8 non acurracy
right?
are maxim insane? heehhe :)
Roberto Spadim escre
does DS2450 an 16bit ad??? or just 16bit ad with 0-5 range? and 8bit
with 0-2.5 range?
i didn't understand, cause in datasheet is write:
User programmable input range (2.56V, 5.12V), resolution (1 to 16
bits) and alarm thresholds
Overdrive mode boosts communication speed to 142k bits per
Roberto,If you are mainly interested in a switch, the DS2408 has 8 switches and is fully supported.If you are interested in thermocouples, the DS27xx family (DS2751 DS2755/6 DS2760/1/2 DS2770 DS2780/1) all have temperature, switch, and thermocouple support built in with known (and commercially avai
Hello guys i was buying ds2405 for input and output, today i bought an
ds2450 for tests.. and it have 4 input and 4 output :D for a cost of 24$
versus 9$ so 4 ds2405 would cost 36$
ok
the question...
now that i will only buy ds2450 :) i want to use ds2450 for some others
things...
could we buil
Thanks Paul! I'll download and check it out.
Jim
Paul Alfille wrote:
> Thanks for picking up that perl error. Fixed in the cvs.
>
> Paul
>
> On 6/10/06, Jim Duda <[EMAIL PROTECTED]> wrote:
>
>>Paul,
>>
>>Ah, thanks for the description, very helpful. I'm almost there.
>>
>>I think I found a p
Thanks for picking up that perl error. Fixed in the cvs.
Paul
On 6/10/06, Jim Duda <[EMAIL PROTECTED]> wrote:
> Paul,
>
> Ah, thanks for the description, very helpful. I'm almost there.
>
> I think I found a possible bug when reading the alarm values through the
> perl interface. I can read the
Paul,
Ah, thanks for the description, very helpful. I'm almost there.
I think I found a possible bug when reading the alarm values through the
perl interface. I can read the voltage, but not the alarm.
When I do a perl get on "volt.X", all is good.
When I do a perl get on "alarm/low.X", I get
On 6/9/06, Jim Duda <[EMAIL PROTECTED]> wrote:
> I measured the DC voltage, and discovered a cold solder joint on the
> PCB. The DS2450 is reading voltage correctly now.
>
> Do the Alarms work? I don't follow how to set and/or detect an alarm.
> I want to know if the voltage drops below 1V DC.
I
I measured the DC voltage, and discovered a cold solder joint on the
PCB. The DS2450 is reading voltage correctly now.
Do the Alarms work? I don't follow how to set and/or detect an alarm.
I want to know if the voltage drops below 1V DC.
I read the documentation, but it wasn't quite obvious wh
Can you test a DC voltage? It's always possible that we aren't reading
voltages correctly.
Paul Alfille
On 6/9/06, Jim Duda <[EMAIL PROTECTED]> wrote:
>
>
> Yes, 60 Hz. I would expect the capacitor to remain at some steady state
> voltage, somewhere around 1.5V. I don't have access to an oscill
Yes, 60 Hz. I would expect the capacitor to
remain at some steady state voltage, somewhere around 1.5V. I don't have
access to an oscillosope at home.
Jim
"Paul Alfille" <[EMAIL PROTECTED]> wrote in
message news:[EMAIL PROTECTED]...
Not
at all off-topic.I'm no expert, but the schem
Not at all off-topic.
I'm no expert, but the schematic is at
http://www.hobby-boards.com/catalog/links/hvac2-r1/HVAC%20Monitor%20v2.0%20Schematic.pdf
With 1M resitor and 1uF capacitor, the time constant is 1 second. What is the frequency of your AC? 60Hz?
Paul AlfilleOn 6/7/06, Jim Duda <[EMAIL
I apologize if this is off topic, since owfs seems to handle DS2450 just
fine, as best I can surmise.
I purchased a "HVAC Monitor Kit" from Hobby Boards. The description of
the board states that it can measure any voltage up to 28V AC or DC.
The design has a diode and a resistive voltage divid
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