Hi.
Yes it is a specific button on the machine. On the original key layout, some modelas had buttons labelled A,B,D,E near the top of the keyboard. These are one-touch clerks, and you just press one of them to log on. Otherwise, you have a clerk button. You need to enter a person's clerk number, then press the clerk button. The default clerk number is 1, but it can be programmed as any secret number you like e.g 1234 clerk. The clerk button often gets re-labelled by people, so they may have called it LOG ON, or STAFF or SIGN ON or PERSON or OPERATOR etc. If you want to try to brute force your way in, then you can press 1 then any button on the keyboard and see if you get in. If not, press clear, then 1 then another button. Try this until you have tried every one of the function buttons (it won't be an item button). If it still doesn't work then there is probably a more complex clerk number programmed, and you will need to look further into the programming. See how you get on.
Mark, September 2008
