Difference between revisions of "RS232 and GPIO Connector"

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(Created page with "The RS232 port can be used to feed the SOUND4 device with UECP commands. Only the RXD/TXD signals are used for UECP, there is no handshaking : the CTS/RTS are not used == Con...")
 
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The RS232 port can be used to feed the SOUND4 device with UECP commands.
+
The RS232 port can be used to feed the SOUND4 device with RDS UECP commands.
 +
 
 
Only the RXD/TXD signals are used for UECP, there is no handshaking : the CTS/RTS are not used
 
Only the RXD/TXD signals are used for UECP, there is no handshaking : the CTS/RTS are not used
  
== Connector ==
+
==Connector==
 
[[File:DB25.png|thumb]]
 
[[File:DB25.png|thumb]]
The DB25-M GPIO+RS232 is compatible with the V.24 standard, "DTE" side, meaning that it's the same as a computer-side connector.
+
The DB25-M GPIO+RS232 is compatible with the V.24 standard, "DTE" side, meaning that it's the same as a computer-side connector.  
 +
 
 
Consequently when connecting a computer to the SOUND4 device, you have to use a Null Modem (cross cable).
 
Consequently when connecting a computer to the SOUND4 device, you have to use a Null Modem (cross cable).
 +
 
So if your PC COM is male SUBD-9, the connection must be at minimum :
 
So if your PC COM is male SUBD-9, the connection must be at minimum :
  
* PC COM DB9M TXD (pin 3) must go to (pin 3) DB25M RS_RXD
+
*PC COM DB9M TXD (pin 3) must go to (pin 3) DB25M RS_RXD
* PC COM DB9M RXD (pin 2) must go to (pin 2) DB25M RS_TXD
+
*PC COM DB9M RXD (pin 2) must go to (pin 2) DB25M RS_TXD
* PC COM DB9M GND (pin 5) must go to (pin 1) DB25M GND
+
*PC COM DB9M GND (pin 5) must go to (pin 1) DB25M GND
  
 
(see [https://en.wikipedia.org/wiki/Null_modem Null_modem wiring diagram])
 
(see [https://en.wikipedia.org/wiki/Null_modem Null_modem wiring diagram])
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'''Notes :'''
 
'''Notes :'''
* the RS232 output voltage is approx. ±6V. Full ±12V is accepted at input.
+
 
* the output RS_TXD pin is not active (so is 0V instead of +6V) until there is activity on RS_RXD pin.
+
*the RS232 output voltage is approx. ±6V. Full ±12V is accepted at input.
 +
*the output RS_TXD pin is not active (so is 0V instead of +6V) until there is activity on RS_RXD pin.

Revision as of 09:55, 22 April 2020

The RS232 port can be used to feed the SOUND4 device with RDS UECP commands.

Only the RXD/TXD signals are used for UECP, there is no handshaking : the CTS/RTS are not used

Connector

DB25.png

The DB25-M GPIO+RS232 is compatible with the V.24 standard, "DTE" side, meaning that it's the same as a computer-side connector.

Consequently when connecting a computer to the SOUND4 device, you have to use a Null Modem (cross cable).

So if your PC COM is male SUBD-9, the connection must be at minimum :

  • PC COM DB9M TXD (pin 3) must go to (pin 3) DB25M RS_RXD
  • PC COM DB9M RXD (pin 2) must go to (pin 2) DB25M RS_TXD
  • PC COM DB9M GND (pin 5) must go to (pin 1) DB25M GND

(see Null_modem wiring diagram)

(Optionally other V24 signals can be connected (CTS, RTS, CD, DSR, DTR) so a fully wired branded Null-Modem cable or adapter should work)

Notes :

  • the RS232 output voltage is approx. ±6V. Full ±12V is accepted at input.
  • the output RS_TXD pin is not active (so is 0V instead of +6V) until there is activity on RS_RXD pin.