Z86017/Z16017 PCMCIA Interface Solution
Product Specification
65
Table 48. Bus Control 1 Register: Address 26h (Continued)
Bit Placement Bit Name
Description
Bit 4
EN_RW_LONG
Set this bit to 1 to enable the read/write long function when
using the 8-bit to 16-bit mode or internal IOCS16
generation in ATA/IDE pass-through mode.
PCMICA 8-Bit to 16-Bit Access After 512 bytes are
transferred, each PC_IOR/IOW strobe to the data register
will generate a ATA_IOR/IOW strobe on the ATA/IDE
bus. 8-bit to 16-bit accesses of the data register will be
continued after any write access to a task file register other
than the data register.
ATA/IDE PASSTHROUGH mode. When set in ATA/IDE
PASSTHROUGH mode after 256 word accesses of the
data register, the //IOCS16 signal on the host interface de-
asserts until the next data transfer phase. The internal
IOCS16 function must also be enabled. (EN_IOIS_IN=1)
and the IOIS16 ADDR register set to 01 pointing to the
ATA/IDE task file data Register 1F0, 170. Clearing this bit
disables the read/write long function.
Bit 6-5
Bit 7
IOIS16_CTRL
BVD_CTRL
IOIS16 source select (see Table 49)
When set to 1, this bit enables the PC_BVD1/STSCHG/
PDIAG and PC_BVD2/SPKR/DASP/DREQ functions.
When cleared, it sets both PC_BVD1/STSCHG/PDIAG
and PC_BVD2/SPKR/DASP /DREQ pins High when in
PCMCIA ATA/IDE memory mode. At Power-On Reset,
set to 0.
Note:
Registers 26h and 27h are only available on the Z16017 device.
Programming Internal Registers
PS012002-1201
ZILOG [ ZILOG, INC. ]
