Just a curiosity. You do not recommend non-oversampling due to personal preference with all DACs or is there something particular with this DAC?
As I understand from posts; one can disable all digital manipulation including oversampling and any filter in your module, correct?
Just in general, I have seen the aliasing products, it's not pretty and can't be a good thing. In my opinion the solution are good filters, not none. Other people seems to have other opinions....
You can bypass/disable all filters in the dac1021, by setting up "bypass" filters in the 1021filt.txt file. You cannot change the rates, the dam1021 will always have the 2.822M/3.072M final sample rate, but t.ex. repeating the same 44.1K samples 64 times is like no oversampling....
It doesn't look right to me.... Why do you have ATE1V1.
That appears to be AT modem config commands E1 = local echo, V1 = English result codes (e.g. CONNECT, BUSY, NO CARRIER etc.), so it doesn't look like you have communication with the DAC.
With the terminal program connected, try restarting the DAC.
You should see something like:
Code:
I3
I1
V-39
L044
V-39This is the DAC reporting back as it checks input 3 then input 1, the current volume setting, the sampling rate and then the volume again....
If you get something like the above you are OK. If you have the V-00, I3 etc you can always try typing I1, I2 or V-99, V-60 etc. If things are hooked up properly , the DAC will respond with the changed settings - if you enter a value which is the same as current setting there will be no response.
Remember also that if you hit return after the "+++" or add an extra + or two it will not work. It must be precisely three "+" and nothing else.
I've attached the settings I use. I'd only use local echo to get started - it makes a mess when you get into uManager.
If you set Xmodem-1K as the default in Transfer Options you can use command-S to start a file transfer, rather than having to navigate to sub menus.
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OK, I've deleted my ZTerm prefs so I'm back to a default state.
The "ATE1 V1^M" is the default modem config.
Go to Settings > Modem Preferences delete everything in the Initialize field, and delete the Dial Substitution strings for good measure. The dial time out can be left, but everything else should be empty as per attached screen shot.
The "ATE1 V1^M" is the default modem config.
Go to Settings > Modem Preferences delete everything in the Initialize field, and delete the Dial Substitution strings for good measure. The dial time out can be left, but everything else should be empty as per attached screen shot.
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Thanks for the clarification.
I am unable to understand that why it is not oversampling if the conversion is not happening at 44.1 kHz.
As per your explanation,
if 44.1 kHz is oversampled 8x to 352.8 kHz and then 8x again to 2.822 MHz then it is oversampling.
But if 44.1 kHz is oversampled 64x directly to 2.822 MHz then it is not oversampling.
I am no expert and thus would really appreciate if you or someone else can help me understand this definitional contradiction.
As I understand it oversampling implies that the signal is filtered or otherwise processed, not just interpolated.
When the signal is interpolated but not modified in any other way this is considered to be upsampling.
So the DAM1021 would be doing x8 oversampling and x8 upsampling.
And going from 44.1 -> 2.822mhz without filtering would be x64 upsampling, not oversampling.
Thank you very much for the detailed and helpful answer. So I deleted everything in the modem preferences and the ATE V1 is gone, but still, no response from the dam1021.
Triple checked the connections (txd to rxd and vice versa), I use a short cable and a logilink usb serial converter with the PL2301TA chip.The driver loads with no problems.
I also tried to access the dam with the terminal screen program with no success.
the attachment shows where I get with typing +++... no sign of the dam1021 :-(
I tend to think it is some kind of hardware problem...
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We actual use the serial port during manufacturing testing, so the serial port works when leaving us....
My experience after selling several hundred thousands of communication computers with serial ports is that 99.999% of serial port problems is incorrect cabling or incorrect terminal setup....
You might want to send a photo of your cabling....
Hi Soeren
Here are three pictures of my connections. txd and rxd are crossed in the cable already, I did not assume that first (I am a total noob with serial connections, never before used one) So I crossed them at the Dam connection but then I did not get a response at all, so I measured the cable and voila, pin 2 and 3 are crossed already and I rectified my cabling accordingly.
I fear I could have damaged something on the board while I have misconnected the cables.
Now I have a response, but it takes the board at least a minute after power cycle to connect to the terminal program and then I still see no uManager, just that curly bracket after the +.
I am obviously stuck, maybe I should try a different usb serial adapter.
Other than that, I really like that DA as is already, definite stepup from what I used to have. But missing the new filter options would be a pity.
Tobias
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Yes, but that is already happening in my serial cable, it is wired pin2 - pin 3.
The dam1021 serial port is wired like a PC's serial port and should be connected to a male dsub9 connector. You would normally need a female to female crossover cable to connect to a PC, or USB adapter emulating a PC serial port. The wiring on your pictures look correct.
Normally, if your USB adapter have a female dsub9 you can plug it directly into a male dsub9, if it have a male dsub9 you need a female to female crossover cable.
It's also important that any terminal program is just in simple terminal mode, no modem mode where it t.ex. might be waiting for dialup.... Again, if using a PC I recommend HyperTerminal.
RS-232 signals are short circuit protected, so I wouldn't expect anything to be damaged.
Off topic :
is there please, a good site to understand the basic of the oversampling vs upsampling, alliasing, etc, stratégies : (Difference with IIR/FIR when speaking of digital filter for a D/A conversion, difference with embeded programated chip, capacity of a fgpa vs a computer doing it on the fly with a soft, etc).
I'm lost reading some saying than doing an upsampling of 16/44.1 can give outstanding result played NOS with the hardware or for some others : upsampled at 354/388 with a pc and a good prioratory soft (Signalyst HQR ?) and played oversampled x2 to x4 max ! Is it just because the best phase noise with low oversampling and in this case the Dam1021 is proof with those defaults because its particular generated FGPA clock ?
Sorry again for the off topic on this busy thread... but a little help to read more elswhere woud be much appreciated
. What are the limitation of the programmation in the FGPA one have to follow in relation to the deep hardware programmation chooses made by Soren (what is writed in stone and can not be changed by the user in this FGPA ?!)
Thank you in advance if anyone has that on hands, (verry interresting thread but difficulty to follow it because the complexity of "digital" conversations ! Take me a lot of time to try to avoid understanding errors !)
regards, Eldam
is there please, a good site to understand the basic of the oversampling vs upsampling, alliasing, etc, stratégies : (Difference with IIR/FIR when speaking of digital filter for a D/A conversion, difference with embeded programated chip, capacity of a fgpa vs a computer doing it on the fly with a soft, etc).
I'm lost reading some saying than doing an upsampling of 16/44.1 can give outstanding result played NOS with the hardware or for some others : upsampled at 354/388 with a pc and a good prioratory soft (Signalyst HQR ?) and played oversampled x2 to x4 max ! Is it just because the best phase noise with low oversampling and in this case the Dam1021 is proof with those defaults because its particular generated FGPA clock ?
Sorry again for the off topic on this busy thread... but a little help to read more elswhere woud be much appreciated
. What are the limitation of the programmation in the FGPA one have to follow in relation to the deep hardware programmation chooses made by Soren (what is writed in stone and can not be changed by the user in this FGPA ?!)Thank you in advance if anyone has that on hands, (verry interresting thread but difficulty to follow it because the complexity of "digital" conversations ! Take me a lot of time to try to avoid understanding errors !)
regards, Eldam
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On my PC I am using PuTTY and ExtraPuTTY (for its XMODEM-1K capability).
I see that for the Mac you can get this version of PuTTY: Spackle | SourceForge.net
Perhaps you should give it a try.
Check tx pin voltage of usb to serial converter. For real rs232 it should be >6V
You might try with an other program e.g. termina/screen (see: http://www.diyaudio.com/forums/vend...magnitude-24-bit-384-khz-142.html#post4215966).
If it fits from the gender, plug the RS232 adapter directely in your DAC plug (then you have do change the wireing again to get the cross over).
I have a short cable, I do not think that is the problem and gender does not fit either, its male to male.
I tried terminal screen, it works untill I want to connect, nothing again.
Should Il try a proven usb to serial adaptor, or are all adaptors with the PL2303TA chip the same and mine should work anyway?
I just had a look at its data sheet and its 3.3 Volts out (I measured again and I had 3.3v not 3.8v I misread it, sorry), so that is all I will have on the pin.
Yeap it's a good question : I tried to have a certified list of prooved USB to serie adaptor in the other thread in first pages for many reasons : some devices are fake, some others don't work with x64 PC or need specific drivers for W.7 & 8...
Mabe a list of needs to choose the device could be helpfull : Bauds speed capacity, etc (Soren said it iirc)? I linked also a brand Trend (not the antivirus )because it seems to be everywhere on Amazon all around the world and cheap ! (10 to 15 euros)
Easy as well like DimDim made to testimonie about its own device when it works ?
Mabe a list of needs to choose the device could be helpfull : Bauds speed capacity, etc (Soren said it iirc)? I linked also a brand Trend (not the antivirus
)because it seems to be everywhere on Amazon all around the world and cheap ! (10 to 15 euros)Easy as well like DimDim made to testimonie about its own device when it works ?