CS494002 datasheet(89/100 Pages) CIRRUS

89 / 100 page

FA1, FSCDIN — Host Address Bit One or SPI Serial Control Data Input

In parallel host mode, this pin serves as one of two address input pins used to select one of

four parallel registers. In SPI serial host mode, this pin serves as the data input. INPUT

FHS1, FRD,FR/W — Mode Select Bit 1 or Host Parallel Output Enable or Host Parallel R/W

DSPAB control port mode select bit 1. This bit is one of 3 control port select bits that are

sampled on the rising edge of RESET to determine the control port mode of DSPAB. In Intel

parallel host mode, this pin serves as the active-low data bus enable input. In Motorola parallel

host mode, this pin serves as the read-high/write-low control input signal. In serial host mode,

this pin can serve as the external memory active-low data-enable output signal.

BIDIRECTIONAL - Default: INPUT

FHS0, FWR,FDS — Mode Select Bit 0 or Host Write Strobe or Host Data Strobe

DSPAB control port mode select bit 0. This bit is one of 3 control port select bits that are

sampled on the rising edge of RESET to determine the control port mode of DSPAB. In Intel

parallel host mode, this pin serves as the active-low data-write-input strobe. In Motorola

parallel host mode, this pin serves as the active-low data-strobe-input signal. In serial host

mode, this pin can serve as the external-memory active-low write-enable output signal.

BIDIRECTIONAL - Default: INPUT

FCS — Host Parallel Chip Select, Host Serial SPI Chip Select

In parallel host mode, this pin serves as the active-low chip-select input signal. In serial host

SPI mode, this pin is used as the active-low chip-select input signal. INPUT

FHS2, FSCDIO, FSCDOUT — Mode Select Bit 2 or Serial Control Port Data Input and Output, Par-

allel Port Type Select

DSPAB control port mode select bit 2. This bit is one of 3 control port select bits that are

sampled on the rising edge of RESET to determine the control port mode of DSPAB. In SPI

mode this pin serves as the data output pin. In parallel host mode, this pin is sampled at the

rising edge of RESET to configure the parallel host mode as an Intel type bus or as a

Motorola type bus. BIDIRECTIONAL - Default: INPUT

FINTREQ — Control Port Interrupt Request

Open-drain interrupt-request output. This pin is driven low to indicate that the DSP has

outgoing control data that should be read by the host.

OPEN DRAIN I/O - Requires 3.3K Ohm Pull-Up

FSCLKN1, STCCLK2

— PCM Audio Input Bit Clock

Digital-audio bit clock input. FSCLKN1 operates asynchronously from all other DSPAB clocks.

In master mode, FSCLKN1 is derived from DSPAB

’s internal clock generator. The active edge

of FSCLKN1 can be programmed by the DSP.

BIDIRECTIONAL - Default: INPUT

FLRCLKN1 — PCM Audio Input Sample Rate Clock

CS494002 Datasheet(PDF) 89 Page - Cirrus Logic