STA310 datasheet(10/90 Pages) STMICROELECTRONICS

10 / 90 page

STA310

10/90

Post Decoding

The post decoding includes specific PCM processing: DC filter, de-emphasis filter, downsampling filter. These

filters can be independently enabled or disabled through the register DWSMODE.

It provides also a Pro Logic decoder, which is described in detail in a next section.

Bass Redirection

This stage redirects the low frequency signals to the subwoofer.

The subwoofer is extracted from the other channels (L, R, C, Ls, Rs, LFe). There are six possible configurations

to extract the subwoofer channel, which can be selected thanks to the OCFG register.

Volume and Balance Control

The volume is a master volume (no independent control for each channel). It is controlled by the PCMSCALE

Two balance controls are available: one for Left/Right channels, one for Left Surround/Right Surround channels.

They are configurable by means of registers BAL_LR (Left-Right Balance) and BAL_SUR (Left Surround-Right

Surround Balance), which provide attenuation of signals by steps of 0.5dB.

OPERATION

4.1 Reset

The STA310 can be reset either by a hardware reset or by a software reset:

- The hardware reset is sent when the pin RESET is activated low during at least 60ns. This is equiv-

alent to a power-on reset.

This resets all the configuration registers, i.e. PLL registers (PLLSYS, PLLPCM), Interrupt registers

(INTE, INT, ERROR), interface registers (SIN_SETUP, CAN_SETUP) and command registers

(SOFTRESET, RUN, PLAY, MUTE, SKIP_FRAME, REPEAT_FRAME).

- The software reset is sent when the register SOFTRESET is written to 1 (the register is automatically

reset once the software reset is performed). It resets only the interrupt related registers (INTE, INT,

ERROR) and the command registers (SOFTRESET, RUN, PLAY, MUTE, SKIP_FRAME,

REPEAT_FRAME). All other decoding configurations are not changed by softreset.

Some information concerning the post-processing are anywayt of date after a soft-reset

Note: 1. The chip must be soft reset before changing any configuration register.

STA310 数据表(PDF) 10 Page - STMicroelectronics