LC89052TA-E Datasheet, PDF (27/42 Pages) Sanyo Semicon Device – Digital Audio Interface Receiver

LC89052TA-E
9 Microcontroller Interface (E/INT, CE, CL, DI, DO)
9.1 Interrupt Output (E/INT)
• The E/INT pin can be set to function as the microcontroller interface interrupt output by setting INTSEL.
• An interrupt output is issued when a change occurs in the PLL lock state or output data information.
• The interrupt output consists of registers for selecting interrupts, the E/INT pin, which outputs those state transitions,
and registers that store interrupt related data.
• The E/INT pin normally is at the low level, and goes to the high level when an interrupt occurs. After going to high
level, it returns to low level according to the INTOPF setting.
• INTOPF determines whether the E/INT pin holds the high pulse for a certain period and is then cleared (returning to
low), or the E/INT pin is cleared at the same time as the output register is read.
• The interrupts can be selected from the sources listed below. More than one items can be set as interrupt sources at the
same time by setting the contents of CCB address 0xEA. The interrupt signal is issued whenever any one of the
interrupt sources arises.
E/INT output = (selected interrupt 1) + (selected interrupt 2) + ... + (selected interrupt n)
Table 9.1 Interrupt Source Settings
No.
Command
Description
1
INTERR
Output when the state of the ERROR pin changes.
______
2
INTPCM
Output when the state of the AUDIO pin changes.
3
INTEMP
Output when the state of the pre-emphasis information changes.
4
INTVFL
Output when the state of the validity flag changes.
5
INTFSC
Output when the input fs calculation result changes.
6
INTCSF
Output when the first 48 bits of the channel status data are updated.
7
INTSQY
Output when the sub-code Q data can be read out.
• The contents of the set interrupt source are stored in output registers DO1 to DO7 at CCB address 0xEB when an
interrupt source arises. However, the registers read for source items 1 through 4 output the current state of those
sources regardless of the E/INT output. For source items 5 through 7, the states are stored when an interrupt source
arises.
• To monitor interrupt source item 5 in the PLL locked state, the oscillator amplifier must be set to continuous operation
mode, since the oscillator amplifier clock is used.
• When the LC89052TA-E is set to the mode in which a H pulse is output from E/INT when an interrupt source occurs,
the pulse width of each interrupt source is somewhere between 1/2 fs and 3/2 fs.
• The action to clear the E/INT pin output simultaneously with the reading of the output registers following the
occurrence of an interrupt is carried out immediately after the output registers at 0xEB are set up. Since, however, the
data associated with interrupt sources 6 and 7 is updated at the intervals listed below, it must be read promptly
whenever the corresponding interrupt sources are detected.
Data
Channel status and preamble B
Sub-code Q data
Table 9.2 Data Update Intervals (Input fs = 32k to 96kHz)
Update interval
2ms to 6ms
13.3ms (fs = 44.1kHz), 6.65ms (2x speed)
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