1997 Jun 16

21

Philips Semiconductors

Preliminary specification

Audio processor for VHS hi-fi

TDA9615H

Table 30 Bit PORR; note 1

Notes

1. Bit POR of the read byte can be used to detect the occurrence of a power-on reset situation (bit POR reads logic 1

used after a power-on reset to force a reset of the POR read bit state to logic 0.

2. POR.

Read byte (device state information)

Table 31 Bits of read byte

Table 32 Bit CALR; notes 1 and 2

Notes

1. Bit CALR = 0 indicates the device is not calibrated. After an automatic calibration is started by setting bit CALS of the

power byte the end of calibration is signalled by this bit. If for some reason a calibration cannot be completed (e.g.

no HID signal available or hi-fi processing is in ‘playback’ mode) CALR remains logic ‘0’. If calibration is lost due to

a power-on reset situation CALR will return to logic 0 as well.

2. Also the envelope output (pin 39) can be used to check for end of calibration.

Table 33 Bit AUTN; notes 1 and 2

Notes

1. When hi-fi processing is in ‘playback’ mode but no hi-fi carrier input signal is detected the auto-normal function is

activated. Auto-normal overrules the ‘Output Select’ mode setting, selecting normal sound (i.e. linear audio) instead

of hi-fi. The state of this auto-normal function can be checked via bit AUTN.

2. The auto-normal function is only active (bit AUTN = logic 1) for hi-fi ‘playback’ mode (bit AFM = 0); during ‘record’ or

‘loop-through’ mode bit AUTN is always logic 0.

PORR

MODE

DESCRIPTION

0

− (note 2)

−

1

POR reset

reset of POR signal bit

BIT

DESCRIPTION

CALR

calibration ready; see Table 32

AUTN

auto-normal; see Table 33

POR

power-on reset; see Table 34

CALR

DESCRIPTION

0

device is not calibrated

1

device has completed auto-calibration

AUTN

DESCRIPTION

0

audio FM signal is detected at FM input

1

no audio FM signal detected; normal sound is selected instead of hi-fi