Howdy guys, I am trying to diagnose a Lunar DPX-SF bone densitometer.
The original issue was that the Reset button was pushed by mistake while the machine was doing its "calibration" and from that point on, the software is not connecting with the machine anymore.
There is an executable which should show the firmware version of the equipment, when run it shows "Invalid response from the SBC-03". If the serial cable is disconnected it takes a while and then says "No response from the SBC-03". So something got corrupted, I don't know if the 6264 RAM could be damaged, or this is a serial comm interface problem. The PC's serial port was tested ok, just in case (tried another PC as well).
I got the CPU board out of the machine and took it to my bench, so I don't have the full machine here, cable harness, nor schematics unfortunately.
I supplied +5, +12 and -12V to power the board, at their respective test points. The problem is that I always get "No response from the SBC-03" on the PC, so I can't continue diagnosing the original issue.
I see a MAX250 and MAX251 combo for serial comms on the mobo. I see ISO +V, ISO -V and ISO GND points in the area, and they go to pins 2, 13 and 14 of the MAX251 respectively. I think I am missing that voltage because of some missing connectors from the main equipment. The question is: is it OK to plug in another 5V PSU in there, to have the serial comms working?
I attach a pic for reference. TIA
The original issue was that the Reset button was pushed by mistake while the machine was doing its "calibration" and from that point on, the software is not connecting with the machine anymore.
There is an executable which should show the firmware version of the equipment, when run it shows "Invalid response from the SBC-03". If the serial cable is disconnected it takes a while and then says "No response from the SBC-03". So something got corrupted, I don't know if the 6264 RAM could be damaged, or this is a serial comm interface problem. The PC's serial port was tested ok, just in case (tried another PC as well).
I got the CPU board out of the machine and took it to my bench, so I don't have the full machine here, cable harness, nor schematics unfortunately.
I supplied +5, +12 and -12V to power the board, at their respective test points. The problem is that I always get "No response from the SBC-03" on the PC, so I can't continue diagnosing the original issue.
I see a MAX250 and MAX251 combo for serial comms on the mobo. I see ISO +V, ISO -V and ISO GND points in the area, and they go to pins 2, 13 and 14 of the MAX251 respectively. I think I am missing that voltage because of some missing connectors from the main equipment. The question is: is it OK to plug in another 5V PSU in there, to have the serial comms working?
I attach a pic for reference. TIA
Comment