1996 Oct 17

11

Philips Semiconductors

Objective specification

DECT baseband controllers

PCD5090; PCA5097

FUNCTIONAL DESCRIPTION

DECT controller system description

The PCX509x is a family of single-chip controllers,

designed for use in Digital Enhanced Cordless

Telecommunications (DECT) systems. The family is

designed for minimal component-count and minimum

power consumption. All controllers include an embedded

The Philips DECT RF-Interface is implemented. The Burst

Mode Logic performs the time-critical MAC layer functions

for applications in DECT handsets and base stations.

The ADPCM transcoding is in compliance with the CCITT

recommendation G.721 and includes receive and transmit

filters.

Power-on reset logic and power management functions

further reduce power consumption and external

components. The chip is intended to support stand-alone

systems only. There are no provisions to build clusters of

base stations. There are no provisions for external

controllers to exert control over the embedded 80C51 or to

have direct access to the on-chip data memories.

The DECT controller consists of a number of functional

blocks that operate more or less autonomously and

communicate with each other via the System Data RAM

(SDR). Blocks have access to SDR via the Internal System

Bus (ISB). The ISB consists of an 8-bit data, a 10-bit

address bus and a number of bus-request/bus-grant

signals. Access to the ISB is controlled by ISB bus

Controller (IBC). The IBC acknowledges bus requests on

the basis of a priority scheme.

The embedded controller 80C51 is to be programmed by

the user. It must contain DECT software from

Man-Machine-Interface (MMI) to the DECT protocols TBC,

CBC and DBC (refer to figures 10, 11, 12 and 13 in

“prETS 300 175-2:1992 section 6”).

All software is available from Philips Semiconductors.

Hardware state machines in the Burst Mode Logic (BML)

and the Speech Interface (SPI) execute the lower blocks in

the TBC, CBC and DBC. The 80C51 has control over the

BML and the SPI via tables in SDR. The BML saves serial

data, received via R_DATAP/M, in buffer areas in SDR.

The position of buffers in SDR is fixed by the 80C51

software by means of tables previously mentioned.

A-fields and B-fields are stored in separate buffers. In this

way, two traffic bearers, each with their private A-fields,

can share the same B-field buffer as is required in case of

bearer hand-over or local call.

The blocks DSP and CODEC support speech processing

functions such as A/D- and D/A conversion, filtering,

ADPCM encoding and decoding, 8-bit A-law PCM to 14-bit

linear PCM conversion and its reverse, echo cancelling,

tone generation, etc.

PCA5097

This chip is intended for program development. It contains

64 kbytes of internal program memory (FEEPROM) for the

80C51 and DSP program RAM.

PCD5090/xxx

This chip is intended for handset and base station

applications. The DSP program is now fixed in a ROM, for

which several ROM codes (/xxx) are available (handset,

analog base, digital base). An external program memory

for the 80C51 of 128 kbytes ROM can be handled.

PCA5097/xxx

This is the same as PCD5090/xxx, but there is 64 kbytes

internal program memory (FEEPROM) for the 80C51.

The DSP program is preprogrammed in ROM.

This chip is meant for development purpose only.