SAA7382 Datasheet, PDF (24/60 Pages) NXP Semiconductors – Error correction and host interface IC for CD-ROM ELM

Philips Semiconductors
Error correction and host interface IC for
CD-ROM (ELM)
Preliminary specification
SAA7382
Table 22 Data transfer control register bits
BIT
FLAG
VERBOSE
7
res.
−
6
DMAMODE DMA Mode Select
5
UDMA
Use DMA
4
SUBIEN SUBI Enable
3
RDRV
Real Drive Select
2
TRANT
−
1
0
DESCRIPTION
reserved
logic 0 = single-word; logic 1 = multi-word
logic 1 = DMA; logic 0 = PIO
logic 1 = interrupt enabled
ATAPI drive number
see Table 23
Table 23 TRANT transfer bits
TRANT
BIT 2 BIT 1 BIT 0
0
0
0
FROM
memory
0
0
1
host
0
1
0
sub-CPU
0
1
1
memory
1
0
0
host
1
0
1
sub-CPU
1
1
x
reserved
TO
host
memory
memory
sub-CPU
sub-CPU
host
reserved
MAXIMUM BYTES
65535 (ATAPI)
32767 (Sanyo)
65535 (ATAPI)
32767 (Sanyo)
−
−
12
12
reserved
NOTES
DMA and PIO
DMA and PIO
−
−
PIO; DBC not used, always 12 bytes
DMA and PIO
−
In the Sanyo and Oak compatibility modes the only transfers are memory-to-host, host-to-memory, sub-CPU-to-memory,
and memory-to-sub-CPU. Setting the TRANT bits to any other settings while in these host modes will cause undefined
results.
1996 Apr 25
24