DESCRIPTION
The PM4388 Octal T1 Framer (TOCTL) is a feature-rich device for use primarily in systems carrying data (frame relay, Point to Point Protocol, or other protocols) over DS-1 facilities. Each of the framers and transmitters is independently software configurable, allowing feature selection without changes to external wiring.
On the receive side, each of eight independent framers can be configured to frame to either of the common DS-1 signal formats: (SF, ESF) or to be bypassed (unframed mode). The TOCTL detects and indicates the presence of Yellow and AIS patterns and also integrates Yellow, Red, and AIS alarms.

FEATURES
• Integrates eight T1 framers in a single device for terminating duplex DS-1 signals.
• Supports SF and ESF format DS-1 signals.
• Supports transfer of PCM data to/from 1.544 MHz system-side devices. Also supports a fractional T1 system interface with independent ingress/egress NxDS0 rates. Supports a 2.048 MHz system-side interface without external clock gapping.
• Provides jitter attenuation in the receive and transmit directions.
• Provides per-DS0 line loopback and per link diagnostic and line loopbacks.
• Provides an integral pattern generator/detector that may be programmed to generate and detect common pseudo-random or repetitive sequences. The programmed sequence may be inserted/detected in the entire DS-1 frame, or on an NxDS0 basis, in both the ingress and egress directions. May be configured to transmit or detect in only the 7 most significant bits of selected channels, in order to support fractional T1 loopback codes in an N x 56kbps fractional T1 setup. Each framer possesses its own independent pattern generator/detector, and each detector counts pattern errors using a 32-bit saturating error counter.
• Provides robbed bit signaling extraction and insertion on a per-DS0 basis.
• Provides programmable idle code substitution, data and sign inversion, and digital milliwatt code insertion on a per-DS0 basis.
• Software compatible with the PM4341A T1XC Single T1 Transceiver and the PM4344 TQUAD Quad T1 Framer.
• Seamless interface to the PM8313 D3MX single chip M13 multiplex and to the PM4314 QDSX Quad Line Interface.
• Provides an 8-bit microprocessor bus interface for configuration, control, and status monitoring.
• Low power 3.3V CMOS technology with 5V tolerant inputs.
• Supports standard 5 signal P1149.1 JTAG boundary scan.
• Available in a 14 mm by 20 mm 128 pin Plastic Quad Flat Pack (PQFP) or an 11mm by 11mm 128 pin Chip Array Ball Grid Array (CABGA) package.

APPLICATIONS
• High density Internet T1 interfaces for multiplexers, switches, routers and digital modems.
• Frame Relay switches and access devices (FRADS)
• SONET/SDH Add Drop Multiplexers