Hello,

I'm running 2.9.26 on HP Vectra P III 800,
and I have connected UPS from APC, Back-UPS Pro 420
on serial port.

I've made cable like one in MikroTik manual,
connected it to serial0, and unhook terminal from serial 0 to make it free.

In winbox I started ups on serial0, what happens is that
routeros finds my ups, and reads out serial, state etc but then after 3-4 seconds it's gone, like ups is not connected.
After few more seconds, it finds him again, and it again dissapears.
Also, winbox shows ups in red color with ! near its name.

Does anyone what why is this happening ?

I've tryed to change serial port properties, but with no results.
Also I tried to change ups with same one, but result is the same.

anyone ?