DWIZ-ADAPT

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Re: DWIZ-ADAPT

Postby GlennGlenn » 21 Aug 2019, 22:14

Woody
:oops:
I thought the DWIZ-ADAPT circuit was doing the level shifting/inversion.
I have ordered the board you mentioned.
Thanks again
Glenn
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Re: DWIZ-ADAPT

Postby woodygb » 21 Aug 2019, 22:25

It is shifting the weird Dynamic signal ...( which is a bit like TTL but at a much higher voltage ...hence the 9.2v zeners) ...to a RS232 signal.
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Re: DWIZ-ADAPT

Postby GlennGlenn » 22 Aug 2019, 20:19

Woody
Further to my question about the caps and theie orientation, I think that if a polarised capacitor is used for C1 its +ve must go to ground.
A negative voltage is taken from the Tx terminal (Rx) and stored in C1. The -ve is used for sending RS232 high from Rx rerminal (Tx).
This is a way of level matching the return -ve voltage to the received one irrespective of what shifting and combination is done by the rest of the adaptor before it goes to remote.
I think I should invert C1 before my RS3232 arrives, do you agree?
Glenn
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Re: DWIZ-ADAPT

Postby woodygb » 22 Aug 2019, 22:23

Not a clue ...sorry.
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Re: DWIZ-ADAPT

Postby Irving » 22 Aug 2019, 22:34

GlennGlenn wrote:Woody
Further to my question about the caps and theie orientation, I think that if a polarised capacitor is used for C1 its +ve must go to ground.
A negative voltage is taken from the Tx terminal (Rx) and stored in C1. The -ve is used for sending RS232 high from Rx rerminal (Tx).
This is a way of level matching the return -ve voltage to the received one irrespective of what shifting and combination is done by the rest of the adaptor before it goes to remote.
I think I should invert C1 before my RS3232 arrives, do you agree?
Glenn

The ground end of c1 should be +ve. C1 and the diode create a TX driven charge pump to provide a -ve reference for the RX circuitry.
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Re: DWIZ-ADAPT

Postby GlennGlenn » 23 Aug 2019, 00:48

Irving
I came to the same conclusion after studying various circuits.
Thanks for the response.
Glenn :thumbup:
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