|You can do it with batch-scripting;|
BUT, this command line tool ISNT built in, so you have to download it.
In this example it does hold down the keys a, b and c for 5 seconds, then it does release it.
nircmd sendkey a down
nircmd sendkey b down
nircmd sendkey c down
nircmd wait 5000
nircmd sendkey a up
nircmd sendkey b up
nircmd sendkey c up
NirCMD can you download at; http://www.nirsoft.net/utils/nircmd...
Happy is ONE who says I am an OttoMAN.