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On runtime, FreeTDM will try to determine (checking the existence of /dev/zap/ctl or /dev/dahdi/ctl) which one you have. In a typical DAHDI installation, the freetdm.conf file will be a basic mirror of the contents /etc/dahdi/system.conf (or /etc/zaptel.conf if using zaptel), but you still need them because they are used by dahdi_cfg or ztcfg to configure the hardware.
Configuration
-> USBFXO
-> AFT analog
-> T1 RBS
DAHDI and Wanpipe Installation
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