got a printer that i need to test for full/half duples functionality as well as 10/100mbps connection

how can I go about testing that the printer is doing either half or full duplex? and that it is in fact set to 10mbps or to 100mbps?
what would be a good way to test this?

Well if your wondering what speed your printer is linking at then it must be a network printer, I would say that plugging it into a switch which has 10/100 and Full/Half Duplex indicators would show you. If your switch doesn't show it then there should be at least a 10/100 led on the printer at the network port.

What kind of printer is it?

But doesnt the led (for either full or half duplex or 10 or 100mbps) on the switch mean that switch's interface itself is able to support either full/half duplex or 10/100mbps? meaning that it doiesnt really tell you if the device's interface which is connected to the switch does support the 10/100mbps or full/half duplex?

the printer is just a generic laser jet 5 with network support

If the switch has LED's for each port showing half or full duplex, 10base or 100base then it should be showing you the link speed of the device attached to that port. Many times you'll have two leds per port which based on color show linkspeed and full/half duplex. One LED usually doubles as an activity LED also, blinking to show traffic and possibly even blinking another color to show collisions.

As far as I know the LaserJet 5 series, and the 5N (being the network enabled model) only support 10Base and probably don't support full duplex.