Hi,
I want to conect my camera to computer. I've read that camera uses TTL signals, while serial PC port uses +/-12V. So I built this adapter. So far it works, but it doesn't provide protection. That's why I tried to build an opto-isolator. I found 2 diagrams using optocouplers but I don't know how to use them.
Opto Isolator 1 seems to be the most convenient, I have the PCB diagram, component layout, component list and most important I can order the PCB very cheap. But the power supply is giving me hard time.
"Power to the PC side of the circuit is derived from the signal lines DTR and RTS. Positive supply is derived from RTS and negative one from the DTR line, therefore it is necessary for the user program to set the RTS status to logic zero & DTR to logic one in order to get the proper supply levels at the output.
How can this be put in practice? How can I make the adaptor using just the power from PC and camera?
Opto Isolator 2 is more complicated because I have just the picture of layout.
In addition I understand from this that a suplimentary power source must be added to the camera side.
Any suggestion is very appreciated. Thanks
I want to conect my camera to computer. I've read that camera uses TTL signals, while serial PC port uses +/-12V. So I built this adapter. So far it works, but it doesn't provide protection. That's why I tried to build an opto-isolator. I found 2 diagrams using optocouplers but I don't know how to use them.
Opto Isolator 1 seems to be the most convenient, I have the PCB diagram, component layout, component list and most important I can order the PCB very cheap. But the power supply is giving me hard time.
"Power to the PC side of the circuit is derived from the signal lines DTR and RTS. Positive supply is derived from RTS and negative one from the DTR line, therefore it is necessary for the user program to set the RTS status to logic zero & DTR to logic one in order to get the proper supply levels at the output.
How can this be put in practice? How can I make the adaptor using just the power from PC and camera?
Opto Isolator 2 is more complicated because I have just the picture of layout.
In addition I understand from this that a suplimentary power source must be added to the camera side.
Any suggestion is very appreciated. Thanks