We are working on communication between AVR and a Crous PTZ.

We can see some details about Crous communication ports on page 15 of its guide :

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We found Crous protocol doc (Got it here) and now we can turn it on and so ... just via Optic port but not RS232 port yet.

These details we applied in RS232 communication:

1 - Crous rs232 is connected to rs232 port of PC and communication has been tested with&without MAX232 .

2 - Ground of Crous power is separate , (PC RS232 & Crous RS232 grounds are connected to each other).

3- All voltages applied are 12 V .

4 -Oscilloscope has been used and it shows only a puls is sent to device but does not show any respond from device

What's your opinion ?why there is no respond on rs232 port?Cours device is new , so is it probable its damaged ?

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    \$\begingroup\$ If the optical connection works, is there any way to have the device send data on the RS232 port by itself? You'll be able to pick up data with the oscilloscope and you'll be able to test your setup and see if the PC can read the sent data. \$\endgroup\$ – AndrejaKo Jan 12 '12 at 13:43
  • \$\begingroup\$ Thanks , as you see in guide , device has a keyboard on it , but when he turns on the device with keyboard there is no wakeup on optic/rs232 port, so we can understand there is no relation between keyboard and ports?on optic work we should send NULL bytes to make it wake up necessarily 100% , how do you think we can have the device send data with out getting wakeup bytes ? \$\endgroup\$ – dehqan Jan 13 '12 at 7:34
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    \$\begingroup\$ Did you try swapping the transmit & receive pins? Whether the equipment is DTE or DCE will determine the configuration of the RS232 port. Sounds simple, but for instance is the Txd the devices transmit? or transmit received from the master? Trying a simple "Null modem" cable will prove that out. \$\endgroup\$ – SteveR Jan 13 '12 at 14:04
  • \$\begingroup\$ I agree with SteveR, and would recommend a SmartCable which deals with switching all of the wiring for you automatically. \$\endgroup\$ – Dave Jun 6 '12 at 20:24

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