TDA7500A

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The features of the EMI are listed below.

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Data bus width fixed at 4 bits for DRAM and 8 bits for SRAM

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Data word length 16 or 24 bits for DRAM

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Data word length 8 or 16 or 24 bits for SRAM

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Refresh rate for DRAM can be chosen among eight divider factor

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SRAM relative addressing mode; 2

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Four SRAM Timing choices

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Two Read Offset Registers

Debug Interface

A dedicated Debug Port is available for each DSP Cores. The debug logic is contained in the core design of the

DSP. The features of the Debug Port are listed below:

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Breakpoint Logic

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Trace Logic

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Single stepping

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Instruction Injection

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Program Disassembly

Serial Peripheral Interface

The DSP core requires a serial interface to receive commands and data over the LAN. During an SPI transfer,

data is transmitted and received simultaneously. A serial clock line synchronizes shifting and sampling of the

information on the two serial data lines. A slave select line allows individual selection of a slave SPI device.

When an SPI transfer occurs an 8-bit word is shifted out one data pin while another 8-bit character is simulta-

neously shifted in a second data pin.The central element in the SPI system is the shift register and the read data

buffer. The system is single buffered in the transfer direction and double buffered in the receive direction.

I

The inter Integrated Circuit bus is a single bidirectional two-wire bus used for efficient inter IC control. All I

bus compatible devices incorporate an on-chip interface which allows them communicate directly with each oth-

er via the I

Every component hooked up to the I2C bus has its own unique address whether it is a CPU, memory or some

other complex function chip. Each of these chips can act as a receiver and /or transmitter on its functionality.

General Purpose Input/Output

The DSP requires a set of external general purpose input/output lines, and a reset line. These signals are used

by external devices to signal events to the DSP. The GPIO lines are implemented as DSP 's peripherals. The

GPIO lines are grouped in Port A which is connected to DSP 0, and Port B, which is connected to DSP1.

RDS

The RDS block is an hardware cell able to deliver the RDS frames through a dedicated serial interface. RDS

quality signalis also available. This block needs to be initialised at reset by the DSP, after that it works in back-

ground and does not need any further DSP support. RDS is made of 57kHz filter, demodulator and decoder.