Hi all,
Thank you for your encouraging words to finish this project asap! It is good to see that there is interest in this USB I/F
Please give me some time. Progress in firmware is substantial, but it is still not in a test-able state.
@ autopoiesis, @ Audio1Man: thanks for the information on how to produce graphs and how to lower the noise floor! It is good to see that Sys1/2 can still be maintained and actually improved. Even if AP does not maintain them anymore (it is their good right after this long time), Sys1/2 are valueable instruments for anyone with serious interest in audio.
@Apogee: Constructive critique is always welcome - you have good eyes. Pin 43 (PA3) and 44 (PA4) are short circuited by intention to have some flexibility in firmware (PA3 is a wakeup pin).
@Analogbuff: The hint with the Tantalum caps is noted. I too have seen tantalum caps fail with a small crater in critical medical systems.
@tomchr: Thanks for the table which AP system is supported by which interface.
It does not make sense to compete with the original AP USB interface for newer Sys2 in my opinion.
@ Audio1Man: That is interesting info regarding the generator output. Can i conclude that the transformer output stage is not the bottleneck of the generator?
Do you think that the MDACs are the weekest link in the generator chain?
R-Udo
Thank you for your encouraging words to finish this project asap! It is good to see that there is interest in this USB I/F
Please give me some time. Progress in firmware is substantial, but it is still not in a test-able state.
@ autopoiesis, @ Audio1Man: thanks for the information on how to produce graphs and how to lower the noise floor! It is good to see that Sys1/2 can still be maintained and actually improved. Even if AP does not maintain them anymore (it is their good right after this long time), Sys1/2 are valueable instruments for anyone with serious interest in audio.
@Apogee: Constructive critique is always welcome - you have good eyes
. Pin 43 (PA3) and 44 (PA4) are short circuited by intention to have some flexibility in firmware (PA3 is a wakeup pin).@Analogbuff: The hint with the Tantalum caps is noted. I too have seen tantalum caps fail with a small crater in critical medical systems.
@tomchr: Thanks for the table which AP system is supported by which interface.
It does not make sense to compete with the original AP USB interface for newer Sys2 in my opinion.
@ Audio1Man: That is interesting info regarding the generator output. Can i conclude that the transformer output stage is not the bottleneck of the generator?
Do you think that the MDACs are the weekest link in the generator chain?
R-Udo
I agree. The AP USB interface is a bit spendy, but about par for the course in the test and measurement world.
Given the relatively low prices on the SYS-1 and SYS-2 (up to the 2300) these days, I bet there is a market for your USB interface. I guarantee you than many people would pay $200-250, if not more, to keep their SYS-1 running...
~Tom
Udo,
it is too easy to get absorbed in "improving" the AP HW, but in my experience the small improvements possible (from already now quite near perfect) are not of great importance in real life. BUT a new USB interface, that is something else.
Please, If I may suggest: focus your energy on the really important USB idea!
it is too easy to get absorbed in "improving" the AP HW, but in my experience the small improvements possible (from already now quite near perfect) are not of great importance in real life. BUT a new USB interface, that is something else.
Please, If I may suggest: focus your energy on the really important USB idea!
I will bet in the first round there will be over 100 people wanting to have this life saver. Once it is known... it is hard to predict, but I would think much more than that. So I could tell you there are lots of eyes looking from the dark, into this thread
Re: bus drive and termination, the official APIB-USB adapter has one 74ACT245 (octal bidirectional tranceiver), two 74ACT240 (octal tristate buffer), two Bourns 4420P-601-250/201 (25 ohm/200pF RCR T-filter), and one Littlefuse SP720ABG (TVS diode array) all crowded around the DB-25 connector.
DC
DC
Thanks for sharing, DC.
Analogbuff: I follow your good advice (and succeeded to 25 %.
The microcontroller firmware is finished (well the first version).
The FX2LP is recognized (enumerated is the right term) by USB bus.
The commands to write data and address bytes, read data bytes and control the status bits is working (and tested with oscilloscope).
I tested the commands with a little helper program to be independent of the Sys1 software.
The missing part is the windows dll to communicate with the Sys1 software.
I hope i find the time to write the interface dll in the coming holydays.
Thx, Udo
Analogbuff: I follow your good advice (and succeeded to 25 %
.The microcontroller firmware is finished (well the first version).
The FX2LP is recognized (enumerated is the right term) by USB bus.
The commands to write data and address bytes, read data bytes and control the status bits is working (and tested with oscilloscope).
I tested the commands with a little helper program to be independent of the Sys1 software.
The missing part is the windows dll to communicate with the Sys1 software.
I hope i find the time to write the interface dll in the coming holydays.
Thx, Udo
I want to share some news:
The USB interface got a big step further to being useable during the last weeks:
- The AP DLL rewrite is nearly finished and the S1 is recognized by the AP Windows Software (tested on Win 7)
- Some simple tests like the analog measurement work as expected.
- The DSP part makes troubles: The DSP is not found by the S1 Software, instead
an error message pops up (there are special DSP related functions in the DLL)
- The hardware need a new layout. Two pins must be swapped (not a big problem) and there
is a HW related problem: if i flash the FX2 when it is still connected to the S1,
i have to do the programming 2x times to be sucessful... have to look into this in detail.
R-Udo
The USB interface got a big step further to being useable during the last weeks:
- The AP DLL rewrite is nearly finished and the S1 is recognized by the AP Windows Software (tested on Win 7)
- Some simple tests like the analog measurement work as expected.
- The DSP part makes troubles: The DSP is not found by the S1 Software, instead
an error message pops up (there are special DSP related functions in the DLL)
- The hardware need a new layout. Two pins must be swapped (not a big problem) and there
is a HW related problem: if i flash the FX2 when it is still connected to the S1,
i have to do the programming 2x times to be sucessful... have to look into this in detail.
R-Udo
You are a genius! You made it so far! You are beating all predictions. It seems like it will be really Happy New Year
I will keep you up to date
As soon as the interface is working without obvious bugs, i am glad for help for further testing.
I have not yet decided if i give away the PCB gerber files and source code or
organize the SMD assembly and give away the finished cable.
Many are not comfortable with SMD soldering and to be honest it is time consuming.
I think that many would prefer a tested and simply working piece of hardware..
Greetings, Udo
As soon as the interface is working without obvious bugs, i am glad for help for further testing.
I have not yet decided if i give away the PCB gerber files and source code or
organize the SMD assembly and give away the finished cable.
Many are not comfortable with SMD soldering and to be honest it is time consuming.
I think that many would prefer a tested and simply working piece of hardware..
Greetings, Udo
Udo,
Hows the project going?
I have a selection of AP systems from a couple of AP1's a SYS2522 & SYS2722 with PSIA etc - and since returning from China I cannot seem to find my PCMCIA cards!
I need to decide what to do as while there is a decent priced LPT to APIB solution available (Audio Precision APIB-LPT Translator kit sold by Audio1man) is only compatible with WIN98SE and I'd like to use the systems on Windows XP machines.
Maybe as you have experience with writing the DLL driver you could offer a DLL driver for the above kit? - I'm sure Audio1Man would be receptive to the idea
I'm located near Brno - Czech Rep. and have a fully equipped lab, if your interested I can help you with the design, testing and manufacture of the hardware, I work with SMD everyday and can arrange multilayer PCB's etc.
I have the equipment necessary in my lab so we can scope the BUS signals on the faster 2722 if you interest etc.
Very keen to buy a couple of interfaces for my AP'1s atleast as I'll soon be setting a small production line / burn in test bench.
Hows the project going?
I have a selection of AP systems from a couple of AP1's a SYS2522 & SYS2722 with PSIA etc - and since returning from China I cannot seem to find my PCMCIA cards!
I need to decide what to do as while there is a decent priced LPT to APIB solution available (Audio Precision APIB-LPT Translator kit sold by Audio1man) is only compatible with WIN98SE and I'd like to use the systems on Windows XP machines.
Maybe as you have experience with writing the DLL driver you could offer a DLL driver for the above kit? - I'm sure Audio1Man would be receptive to the idea
I'm located near Brno - Czech Rep. and have a fully equipped lab, if your interested I can help you with the design, testing and manufacture of the hardware, I work with SMD everyday and can arrange multilayer PCB's etc.
I have the equipment necessary in my lab so we can scope the BUS signals on the faster 2722 if you interest etc.
Very keen to buy a couple of interfaces for my AP'1s atleast as I'll soon be setting a small production line / burn in test bench.
John, better ask audio1man,
but as I recall, although needing W98 , the currently most $$ reasonable solution,
the LPT-Apib SW and cable available from audio1man
relies on some special LPT access particular to the Win98 OS, & sadly not present in XP .
With all the brainpower & talent present here, ,if this was a relatively simple procedure you´d think that someone had already nailed this one.
But if all those with some knowhow of the AP interface pooled your combined insight, in a group project effort, maybe...
I pin my hopes on Udo - just so you know it ;-) ,
I believe a lot of followers are waiting for you to break through to XP for older AP sys1, and 2´s owners .
I don´t care if it´s in a neat and tiny cable D25 head, or in an ugly I/F box - as long as it gets the job done!
As a kit or a semi-finished kit (ie. SMD done) selling a 1-200 Euro´s , I think it could be well worth your time.
UDO !!! please keep the pot bubbling !
best.
but as I recall, although needing W98 , the currently most $$ reasonable solution,
the LPT-Apib SW and cable available from audio1man
relies on some special LPT access particular to the Win98 OS, & sadly not present in XP .
With all the brainpower & talent present here, ,if this was a relatively simple procedure you´d think that someone had already nailed this one.
But if all those with some knowhow of the AP interface pooled your combined insight, in a group project effort, maybe...
I pin my hopes on Udo - just so you know it ;-) ,
I believe a lot of followers are waiting for you to break through to XP for older AP sys1, and 2´s owners .
I don´t care if it´s in a neat and tiny cable D25 head, or in an ugly I/F box - as long as it gets the job done!
As a kit or a semi-finished kit (ie. SMD done) selling a 1-200 Euro´s , I think it could be well worth your time.
UDO !!! please keep the pot bubbling !
best.