To answer your question, yes, it is difficult. GDS is designed to be a SIP door phone, as well as door opening access via PIN.
Thinking yourself as GDS, if using keypad as the ONLY interface to outside, what can you tell if the digits inputted is a PIN to open door or a number to make call ? (if digits are the only instruction you get from outside)? As you mentioned, what can you tell the input 1234 is a PIN or a phone number?
If you are using RFID card, no problem, the input is via scanner (not keypad, different input method) and the device know this is for open door and will match the inside DB if good then door opened.
That is why <*> is designed to put before the digits, telling device this is a PIN input not a call input.
For your case, if you assign a user with a RFID card, in the “Card Management” page, you can assign the card with unique Virtual Number (could be Room Number in Apartment) or SIP extension number, and Private PIN. And select “Local PIN Type” to be “Private PIN” telling GDS everyone has own PIN. Then you can either swipe card to open door or use private PIN to open door, using format: Asterisk Virtual_Number_OR_SIP_Extension Asterisk PrivatePIN #. The first Asterisk is telling GDS this is a PIN input, the 2nd Asterisk is just separator of the PIN and Extension/Room (which the extension/room identifies user in the Event Notification for 3rd party software because PIN should not be sent out for security reason). The last ‘#’ is just return key (like computer, the GDS in reality is an embedded mini computer). In my case, I use last 4 or Birthday as employee’s Private PIN so everybody will know themselves and their SIP extension (I have GDSManager collect the GDS event and log so I will know who and when entering the door, 3rd party software can also do this kind of HR related things by collecting event log with time stamp)
So, for example, anyone come to the door phone, press “doorbell” will ring someone, or dial “0” to call operator, or dial extension (ending with ‘#’) if knowing what extension to call (This is good for a building with different companies application scene, visitors call different number to reach different company operator from door). If employee forgot to bring RFID card, use your example, just dial: asterisk111asterisk1221# to open the door. In this example, “111” is the SIP extension number or room number, “1221” is the person’s last 4 or birthday known to self. ‘#’ just as return to finish the input, I did not see any difficulty to remember those digits here for the user, but very difficult for hacker or person want to try and error PIN from the door because the PIN is now having special character combination not just digits (like old system), and trying too many times with error PIN will trigger GDS to send Alarm to administrator (if enabled and configured this feature).
Now, if you don’t want GDS function as door phone (meaning nobody can make phone calls from keypad), only want PIN as input from Keypad, the latest firmware 220.127.116.11 implement “Disable Keypad SIP Number Dialing”, once you enabled this, the GDS will just function like old system, input (PIN#) will open door, because device know any digits input via keypad is for PIN, and (#) is enter like computer. If you do this (most customers will also select lock keypad input when using this way), then only call GDS can make is via pressing doorbell button, which is your pre-programmed SIP extension(s) or IP address(es). The private PIN is configured in the “Card Management” tab and you can assign different PIN to different users.
Hope this answers your question. There are lots of features for you to exploit and integrate with your customer’s application solution, like HTTP API. Thank you for using GDS3710,