There has already been some discussions about the serial port about being TTL or not and apparently being 3,3 Volt level.
Is it correct that what we need is actually an USB to UART interface ?
The typical thing is that UART has never really been mentioned here so I am in doubt.
I think I should order something llike this:
CP2102 USB UART Board (type A) CP2102 USB to UART Module, USB type A connector
Is this correct ?
Is it correct that what we need is actually an USB to UART interface ?
The typical thing is that UART has never really been mentioned here so I am in doubt.
I think I should order something llike this:
CP2102 USB UART Board (type A) CP2102 USB to UART Module, USB type A connector
Is this correct ?
I connected with Putty to the dac and get this information .. anybody seen this before ?
I have only powered VCC5D (both pins in J2 and GND of course) and connected COM_RXD, COM_TXD and GND, no other connections for now.
When I start PuttY first and then power up the DAC it gets connected and get this information:
I have only powered VCC5D (both pins in J2 and GND of course) and connected COM_RXD, COM_TXD and GND, no other connections for now.
When I start PuttY first and then power up the DAC it gets connected and get this information:
I used my oscillioscope to measure some signals becuase there was some discussion about serial being 3,3V level and I am not 100% sure about mine PL2303.
On the DAC I measure on COM_TXD 3,2 Volt level with signal (pulse) going to 0V when Putty receives some data from the DAC.
The COM_RXD is however approx -4,4 V (minus !!) with no data (or too short to pick up).
The minus 4,4 Volt on RXD confuses me ... TXD suggest I hhave 3,3 Volt level.
P.S. thinking about it ...
RXD is what my USB-RS232 converter sends to the DAC which could be based on 5 Volt level measuring - 4,4V
TXD is what the DAC sends out ... as the DAC is 3,3 Volt level the measured 3,2 Volt makes perfectly sense.
I guess I will need to find a 3,3 Volt level RS232 to make this work ?
On the DAC I measure on COM_TXD 3,2 Volt level with signal (pulse) going to 0V when Putty receives some data from the DAC.
The COM_RXD is however approx -4,4 V (minus !!) with no data (or too short to pick up).
The minus 4,4 Volt on RXD confuses me ... TXD suggest I hhave 3,3 Volt level.
P.S. thinking about it ...
RXD is what my USB-RS232 converter sends to the DAC which could be based on 5 Volt level measuring - 4,4V
TXD is what the DAC sends out ... as the DAC is 3,3 Volt level the measured 3,2 Volt makes perfectly sense.
I guess I will need to find a 3,3 Volt level RS232 to make this work ?
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I received the TTL serial converter and works perfect.
DEBO USB2UART 1: Ontwikkelaarsboards - USB type A op UART, PL2303 bei reichelt elektronik
Set to 3,3 Volt by jumper and finally got the correct information at startup.
I also upgraded the firmware to 1.21
In the delivery with the TTL converter were also the parts to build the power supply and make all the connections to a BeagleBone Black and put it all in an enclosure.
Hopefully I will have it running this week
DEBO USB2UART 1: Ontwikkelaarsboards - USB type A op UART, PL2303 bei reichelt elektronik
Set to 3,3 Volt by jumper and finally got the correct information at startup.
I also upgraded the firmware to 1.21
In the delivery with the TTL converter were also the parts to build the power supply and make all the connections to a BeagleBone Black and put it all in an enclosure.
Hopefully I will have it running this week
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Now that I updated the firmware I can continue with the build.
I already did some details some month ago like the PCB holding the transformers:
This is how the power supply design wil look like:
I now bought a Modu Galaxy enclosure and decided to install everything to an aluminium plate acting as divider and put it vertical, some treaded rods wil hold everything in place.
I still need to build the rectifier boards with the main capacitors.
I also included some rubber grommets for the wiring going to the other side of the divider.
Here I already installed the LAN + USB cable to the rear panel:
The BeagleBone Black will also receive an add-on board with dual clocks and I2S isolator. This is now installed in my main system so the build you see here is with my spare BeagleBone Black.
I still need to include a Toslink reciver so my TV sound will also run over the Soekris DAC instead of the lower quality line-out into my pre-amp.
I want to include the Toslink input later when I have ordered a new custom rear panel from Shaeffer or similar company.
I already did some details some month ago like the PCB holding the transformers:
This is how the power supply design wil look like:
I now bought a Modu Galaxy enclosure and decided to install everything to an aluminium plate acting as divider and put it vertical, some treaded rods wil hold everything in place.
I still need to build the rectifier boards with the main capacitors.
I also included some rubber grommets for the wiring going to the other side of the divider.
Here I already installed the LAN + USB cable to the rear panel:
The BeagleBone Black will also receive an add-on board with dual clocks and I2S isolator. This is now installed in my main system so the build you see here is with my spare BeagleBone Black.
I still need to include a Toslink reciver so my TV sound will also run over the Soekris DAC instead of the lower quality line-out into my pre-amp.
I want to include the Toslink input later when I have ordered a new custom rear panel from Shaeffer or similar company.
I am getting closer to a working DAC
Unfortunate I did not have any LM317T left for the BBB power supply so need to order some extra pieces.
Need to order a Toslink receiver anyway so I am collecting parts for a complete order.
Did finish the power supply board with the 4 rectifiers and RC filters / capacitors which will feed the LDO's for the DAC and the LM317.
I also added a "service port" so I can easy connect via the serial interface later if needed.
GTR stands for Gnd/Tx/Rx
Unfortunate I did not have any LM317T left for the BBB power supply so need to order some extra pieces.
Need to order a Toslink receiver anyway so I am collecting parts for a complete order.
Did finish the power supply board with the 4 rectifiers and RC filters / capacitors which will feed the LDO's for the DAC and the LM317.
I also added a "service port" so I can easy connect via the serial interface later if needed.
GTR stands for Gnd/Tx/Rx
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Finally I had al the parts and time to finish the build.
The add-on board for the BeagleBone Black with dual XO, I2S isolator and related parts.
The other side with the dam1121:
The 3,3 Volt for the I2S isolator is done by 2 diodes in series finally getting 3,6 Volt which is fine too.
A bit cramped but it all fits nicely:
Unfortunate I did not realise that the capacitors on the rectifier board is blocking the USB port so I can not attach the short USB cable to the rear panel.
Not really a big problem but would nice to have to mount any USB stick and play it directly via the BBB.
Music is playing nicely while I am typing this post
The add-on board for the BeagleBone Black with dual XO, I2S isolator and related parts.
The other side with the dam1121:
The 3,3 Volt for the I2S isolator is done by 2 diodes in series finally getting 3,6 Volt which is fine too.
A bit cramped but it all fits nicely:
Unfortunate I did not realise that the capacitors on the rectifier board is blocking the USB port so I can not attach the short USB cable to the rear panel.
Not really a big problem but would nice to have to mount any USB stick and play it directly via the BBB.
Music is playing nicely while I am typing this post
I tend to have some trouble with hash noise with USB on my Linux based pc so I decided to buy the DIYinHK optical receiver just to try for more connection options, its a single wire directly feeding the DAM about 20cm long, plus of course the 3.3v pins to power it, to me it sounds better maybe its because its much simpler than the Xmos which costs a lot more compared to $10 and just as good if not better than Xmos in my opinion.
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toslink to a DAM dac is a really god idea as you get isolation. The old speak that opto is bad was due to the poor receivers / PLLs so that all the jitter from the limited interface effected the performance of the DACs. Nowadays, with PLLs as in the DAM dac (could and will apparently be improved ) , the opto becomes an advantage over all other interfaces if you can be satisfied with 24/192 as maximum...
Toslink is great!
//
) , the opto becomes an advantage over all other interfaces if you can be satisfied with 24/192 as maximum... Toslink is great!
//
TNT do you know what frequency the si570 outputs when playing from the i2s input?
The reason I’m asking: I’m thinking about sourcing the dam1121 with Andreas master clocks. The idea is to attach a si570 to the dam1121 via i2c which will in turn power off the on board si570 and accepts the incoming lvds signal. But instead of feeding the lvds from the external si570 I will feed a lvds signal that I derived from TWTMC converted though an e.g. an idt 8t39204.
As I always know the SR of the incoming i2s signal it should be no problem to select between 44/48. As I don’t need spdif input I should not need other frequencies. The only quenstions here is what frequency does the dam1121 need when playing 44khz respectively 48khz i2s signals.
Greetings,
The reason I’m asking: I’m thinking about sourcing the dam1121 with Andreas master clocks. The idea is to attach a si570 to the dam1121 via i2c which will in turn power off the on board si570 and accepts the incoming lvds signal. But instead of feeding the lvds from the external si570 I will feed a lvds signal that I derived from TWTMC converted though an e.g. an idt 8t39204.
As I always know the SR of the incoming i2s signal it should be no problem to select between 44/48. As I don’t need spdif input I should not need other frequencies. The only quenstions here is what frequency does the dam1121 need when playing 44khz respectively 48khz i2s signals.
Greetings,
toslink to a DAM dac is a really god idea as you get isolation. The old speak that opto is bad was due to the poor receivers / PLLs so that all the jitter from the limited interface effected the performance of the DACs. Nowadays, with PLLs as in the DAM dac (could and will apparently be improved
Toslink is great!
//
Same here with a DAM1021, toslink (diyinhk) sounds better than usb (Amanero).