I realise that this question was posed a while ago but for the benefit of the rest of the people who may want to know. Here it is.
Yes, you can use a standard null modem cable to connect directly to the unit using hyperterminal.
1. Connect the EOC-3220 to your computer with the null modem serial cable.
2. Start a HyperTerminal session: Click Start and then select Programs -> Accessories -> Communications -> HyperTerminal.
3. After the HyperTerminal window appears:
a. Give this new connection a name. Ex: EOC-3220.
b. Select correct COM port. Ex:COM1.
c. Set baud rate as "38400", data bits "8", parity "none", stop bits "1", and flow control as "None". Then press “OK” to bring up the HyperTerminal window.
d. unplug the power on the POE injector wait 5 seconds and plug it back in.
4. Wait until the "#" is displayed in the HyperTerminal window.
5. Type "flash reset", then hit enter.
6. Type "reboot", then hit enter. After the device reboots, all settings will be at factory default.
PS: You can either buy a null modem serial cable or you can make your own if you have all the equipment needed.
http://www.shopmania.co.za/shopping~online-cables-adapters~buy-manhattan-db09f-db09f-serial-null-modem-cable-es360302~p-1005256.html