Where are you seeing a requirement for an 8 digit PIN? The HT2000W modem has a WiFi access password on the sticker, which should be either on the back or bottom of the unit.
You can also see the WiFi access password(s) by using a LAN cable connected device to go to http://192.168.42.1/login.htm, and use admin as the password to sign in. You can see the WiFi access password there for each radio (it's the same for each by default), and change them if you wish.
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