but in practice, in the Philips OM5284 what would it be, you wrote the instructions of the axis control of the mechanics or you wrote the entire firmware of the CD controller?
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This is the same function as your HECD-019A, it is connected to the MCU of the CD player through the DSA interface, and it controls the SAA7372 through I2C, the advantage of using DSA is that it does not need to pay attention to any servo parameters, for example, you write a 0x03 through DSA to OM5384, this board will start reading TOC, and ready to play, as long as the instructions are read and written, and it can be compatible with very old chip solutions, such as the SAA7345 of CDT612.
I just tested it and I made a big discovery! The board using SAA7372 uses I2C communication to be fully compatible with SAA7327! This is something I've always wanted to test, tried it today, it's the same! In other words, OM5284 can replace your P87C58! But there is a difference in wiring because the OM5284 uses SILD and RAB, just like the circuit of the CDT-713 I attached! Like datasheet, the SAA7327 is just adding some new registers to the SAA7372! The software is compatible!
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So there is no need to write anything inside the OM5284?
And the SAA7372 which generates the instructions for the OM5284 and which are sent through the SILD and RAB ports?
It's correct?
the OM5284 is a MCU with mask rom, it has been programmed already！ And there are versions on the chip, which says CDT713 V1.0, this is the software version of the software inside this chip. I had try a SAA7372 board works in a CDP with SAA7327, without any modify! so I think this OM5284(CDT713) can also control the SAA7327!
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I've checked the pins of the two, P87c58 and OM5284, they're pretty much identical so I'm convinced it's working. Now I just need to find some OM5284's.
Thanks so much for the great information.
Thanks so much for the great information.
have you copy the sch of HECD-019a? the SCH depends on the software! so you need to check the sch of HECD-019A!
As can you see the only connected pin is pin 20 (TRAY SW).
The circuit of pin 20 of the P87c58 arrives at a C945 transistor, at a 4.7k resistor, at the positive of a 1uF capacitor, at pin 3 of the 4-pole connector of the drawer opening closing control (TRAY SW).
The circuit of pin 20 of the P87c58 arrives at a C945 transistor, at a 4.7k resistor, at the positive of a 1uF capacitor, at pin 3 of the 4-pole connector of the drawer opening closing control (TRAY SW).
Remade the PCB with SMD components and made some modifications.
Added TDA7073, SAA7372 and OM5284. Added IN and OUT (I/O crystal/resonator).
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I'm just curious, why do you want this board to work on the DSA interface, because your control program is DSA?
The connection pins between the controller and servo PCB are exactly the same.
As you can see the schematic of the SERVO you kindly sent me and the HECD-019A are the same.
The SDA and SLC communication ports are the communication ports between SAA7372 and OM5284 in the case of the schematic and SAA7324 and P87C58 in the case of the HECD-019A.
So I should just check if my CD PLAYER controller is compatible with the SAA7372-OM5284 "pair", if the firmware data of the P87C58 is the same in the OM5284 (CDT713 V1.0) unless you have already tried it.
As you can see the schematic of the SERVO you kindly sent me and the HECD-019A are the same.
The SDA and SLC communication ports are the communication ports between SAA7372 and OM5284 in the case of the schematic and SAA7324 and P87C58 in the case of the HECD-019A.
So I should just check if my CD PLAYER controller is compatible with the SAA7372-OM5284 "pair", if the firmware data of the P87C58 is the same in the OM5284 (CDT713 V1.0) unless you have already tried it.
HECD-019A PIN ----> GNDM (GND) - +9v - +5v - GND - MISC - SCLK - WCLK - DATA - AUXBACK (ACK) - AUX1DATA (DAT) - AUX3STB (STB) - RST (RESET) - GNDM (GND)
SCHEMATIC PIN ----> GND (GNDM) - DATA - WCLK - SCLK - MISC - ACK (AUXBACK) - DAT (AUX1DATA) - STB (AUX3STB) - RESET (RST) - GND - GND (GNDM) - +5V - +9V
Yes, I've tried, as you know, I have a HECD-019A, removed from cyrus CD8, I put inside a CDP using the DSA interface of OM5284 and it works perfectly!
Well!
As soon as the PCB is mounted I will let you know.
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Great project. I have a Musical Fidelity A5-CD that sports this loader. Unfortunately a bad 7805 regulator has destroyed functionality of mainboard, display and servo board injecting about 12V on the +5v digital line. :-( I'd like to restore and the only part very difficult to repair is this servo board. It seems that is not simple to find. Let us update on your project. Thanks
