W88113C Datasheet, PDF (41/102 Pages) Winbond – ATAPI CD-ROM DECODER & CONTROLLER

W88113C
SCIACK - Subcode Interrupt Acknowledge - (write 22h)
Writing any value to this register de-activates SCIb (01h.r0) if SCIEN (2CH.w4) is enabled.
SUBSTA - Subcode Status Register - (read 22h)
When SCIb (01h.r0) is activated, the microprocessor can read this register to determine the reason of
interrupt.
Bits 7-5: Reserved
Bit 4: QCRCOK - Q-channel CRC OK flag
If Q-channel extraction is enabled, this bit reflects the status of CRC checking of Q-channel
information.
Bit 3: reserved
Bit 2: MSS - Missing Subcode Sync
A missing-subcode-sync sets MSS high and negates SCIb (01h.r0). A microprocessor
interrupt is activated also if SCIEN (2Ch.w4) is enabled.
Bit 1: NESBK - Normal End of Subcode Block
A normal-subcode-block-end sets NESBK high and negates SCIb (01h.r0). A microprocessor
interrupt is activated also if SCIEN (2Ch.w4) is enabled.
Bit 0: ISS - Illegal Subcode Sync
An illegal-subcode-sync sets ISS high and negates SCIb (01h.r0). A microprocessor interrupt
is activated also if SCIEN (2Ch.w4) is enabled.
TBH/L - Transfer Block Register - (read/write 25h/24h)
If LATXF (03h.7) is low, TBH/L form a 9-bit counter that is used to specify the first RAM block to be
transferred, while registers TACH/L (05h/04h,w) specify the starting address relative to the beginning
of this RAM block. The block-offset transfer is carried within a transfer ring that is controlled by
DTRCH/L (53h/52h) and DTRBH/L (51h/50h). The buffer ring and transfer ring are usually defined in
the same range.
Note that TBH/L (25h/24h) do not increment automatically at the end of each transfer unless:
• ACMEN (9CH.6) is high
• DINB (1Fh.1) is low (data-in transfer is enabled)
• LATXF (03h.7) is low (block-offset transfer is used)
If ACMEN (9Ch.6) is high, TCC (9Dh) minus N and TBH/L (25h/24h) plus N right after SKIPC (9Eh) is
set N.
If BICEN (9Ah.7) is high and BCFSEL (9Ah.5) is low, the DSP buffering stop when buffering block
(internal) reach TBK (9Bh,w).
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Publication Release Date: Mar. 1999
Revision 0.61