Hi everyone! recently got an old pair of altec lansing 8558B microaudio 28 band programmable equalizers and a POD programmer model 28R from microdaudio. I had in mind to incorporate such EQ to my current system. The problem is: I can not set the frequencies due the DB9 cable is missing. I tried with a pin to pin cable (1-1,2-2, 3-3 and so on) and the programmer turns on and seems like it is working but there's no communication with equalizers. It shows the frequencies and levels are moving but not for real. No change on sound. Pins for ground and Vcc are okay , probably more than 3 pins match with position, however the programming can not be achieved. I drew a short schematics based on both Db9 terminals and still not clear. Does anybody know the pin configuration for this cable? thank you.
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Here is a data sheet:
http://alteclansingunofficial.nlenet.net/proelectronics/equalizers/8553B-Data.pdf
Here is the 422 wiring:
https://www.atlasied.com/d/IED_Downloads/590I_3_52b.pdf
Note the crossover connections!
http://alteclansingunofficial.nlenet.net/proelectronics/equalizers/8553B-Data.pdf
Here is the 422 wiring:
https://www.atlasied.com/d/IED_Downloads/590I_3_52b.pdf
Note the crossover connections!
Thank you Simon, the RS422 protocol is not suitable for this MicroAudio interface, its proper for the PC programmer and 8061 adapter and Altec's System 422 . For the 8055B and 8051a and MicroAudio 28R must be " uA- bus " according with the manual and the cable is a " non TTL , 9 pin D subminiature " so, "non TTL" says nothing, its doubtful no accurate. I will upload the drawings I made by hand.
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Those are the simple drawings for the internal connection. As you guys can realize at the side of the MicroAudio programmer the most of the connections go to the INput pins of the U6 ( 74hc365 buffer ) and OUTput pins of the U5. So, those lines are bidirectional just at one time one direction. The U5 into the MicroAudio programmer seems to be controlled by the Equalizer through pin 8 of DB9, but at the same time seems like the Equalizer U8 is also controlled by the Micro Audio Programmer by pin 8 through DB9, that makes no sense since I don't see any signal present checking by the oscilloscope means. So I am lost, I don't know where to go to ...your help is highly valuable on this.
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