TDA1373H Datasheet, PDF (19/40 Pages) NXP Semiconductors – General Digital Input GDIN

Philips Semiconductors
General Digital Input (GDIN)
Product specification
TDA1373H
Table 7 Overview of selectable CUP functions
SM1
SM0
LR⁽¹⁾
CUP FUNCTION
0
1
0 extract full C-block left (192 bits/block)
0
1
1 extract full C-block right (192 bits/block)
1
0
X extract full U-block (384 bits/block)
0
0
X decode CD-Subcode Q-information (80 bits/CD frame) from U-bits
Note
1. X = don’t care.
RAM BUFFER
80H to 97H
80H to 97H
80H to AFH
80H to 89H
The extracted or decoded information can be read in three
ways:
• From the internal RAM buffer by a microcontroller
(see Section “The RAM buffer”)
• At the output pins CUS, BS and CEN (see Fig.11)
• In status registers STS5 and STS6 (permanent 16
‘consumer mode’ C-bits, see Table 9).
During CD subcode Q extraction, a 16-bit CRC is done
over the Q-channel (CRC flag). This flag is only
meaningful when the ADIC is locked (LCK flag).
THE RAM BUFFER
A double RAM buffer is present in the device. While
reading one buffer, the other buffer is filled with the new
incoming data. The RAM buffer can be read in two ways:
1. Interrupt protocol (UIP = 0).
2. User request protocol (UIP = 1).
Interrupt protocol (UIP = 0)
A C-block, a U-block or CD Subcode frame is read in the
time between two Block Sync (output pin BS) pulses,
which can be used as the interrupt for a microcontroller. At
a sample rate of 44.1 kHz, the microcontroller must be
able to read a C-block or U-block within _{4----14---91---20----0--} = 4.35 ms.
CD Subcode frames are received at a data rate of 75 Hz
or 13.3 ms/frame.
User request protocol (UIP = 1)
The microcontroller requests for a C, U and CD-Q block or
frame, which will then become available at the next block
preamble, indicated by BS. The information is not updated
until the next user request, which means the
microcontroller can take any time to read the information.
The CD Subcode CRC check flag always shows the CRC
over the last received CD Subcode Q frame and is not
stored with the present Q frame in the buffer. Figure 12
shows the user request read procedure.
1996 Jul 17
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