The DS2154 is a second-generation line interface unit for E1 lines. It is pin- and software-compatible with the first-generation DS2153Q and function- and pin-compatible with the DS2152, its T1 counterpart. The DS2154 retains all features of the DS2153Q adding crystalless jitter attenuation, additional hardware signaling, a full HDLC controller for the FDL layer with 16-byte buffers, and the option for nonmultiplexed bus operation.
The DS2154 meets E1 specifications, including ETS 300 011, 300 233, 300 166, TBR 12, and TBR 13 and ITU G.703, G.704, G.706, G.823, and I.431.
Through the parallel port, the user can quickly access the 8-bit internal registers and configure the DS2154 to the application under processor control.
主な特長
Complete E1(CEPT) PCV-30/ISDN-PRI transceiver
Long- and short-haul line eterface for clock/data recovery and waveshaping
32-bit or 128-bit crystalless jitter attenuator
Generates line buildouts for both 120Ω and 75Ω lines
Frames to FAS, CAS, and CRC4 formats
Dual elastic buffers connect to asynchronous backplanes up to 8.192MHz
8-bit parallel control port can be used directly
Parallel port can also be muxed or nonmuxed to bus
Extracts/inserts CAS signaling
Detects/generates remote and AIS alarms
Progammable output clocks for Fractional E1, H0, and H12
Independent transmit/receive functions
Full access to both Si and Sa bits aligned with CRC multiframe
Four testing loopbacks
Large error counter for bipolar and code, CRC4 code/word, FAS, and E-bits