Panasonic KX-TD1232JT Programming Manual page 263

• For the KX-TD1232, port numbers 01 through 06 are for the Master System and 07 through
12 are for the Slave, if available.
• This programme becomes available when "MSN" is selected in programme [452-
453] ISDN Ring Service Assignment – Day / Night.
Features Guide References
Integrated Services Digital Network (ISDN)
Multiple Subscriber Numbers (MSN) Ringing Service
ISDN Programming
3.3 ISDN Line Programming
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