Z86017 Datasheet, PDF (51/138 Pages) Zilog, Inc. – PCMCIA Interface Solution

Z86017/Z16017 PCMCIA Interface Solution
Product Specification
37
Table 11. Interface Configuration Register: Address 00h (Continued)
Bit Placement Bit Name
Bit 4
EN_RDY_BSY
Bit 5
EN_CTR_IRQ
Bit 6
EN_INT_POL
Bit 7
EN_ATA_BHE
Description
When this bit is set to 1, the PC_RDY/BSY/REQ/HINT
pin is configured as RDY//BSY. To con•gure this pin as an
IREQ/HINT, set this bit to 0. On Power-On Reset, the
ZX6017 automatically reads the EEPROM and also
determines if a PCMCIA device is connected. After the
entire attribute memory is loaded and the chip initialization
is complete, the READY/BSY signal on the PCMCIA bus
indicates READY. Without an EEPROM, the device
indicates READY whenever this bit is set and the ZX6017
has determined a PCMCIA bus is connected.
Enables PCMCIA Interrupt Mode. Enables ATA_IREQ pin
to control PC_IREQ in I/O Mode. This bit is active when
set to 1. On Power-On Reset, this bit is set to 0.
Enable local (M_PINT) processor interrupt polarity active
Low. This bit is active when set to 1. On Power-On Reset,
this bit is set to 0. Interrupt is active High. M_PINT is a tri-
state driven signal. Whenever an interrupt is present and
enabled, M_PINT is driven. If the interrupt is programmed
active High, then M_PINT is driven from tri-state to High.
If the interrupt polarity selects active Low interrupts, then
the interrupt is driven from tri-state to active Low. Also see
Register 2Ch.
When this bit is set to 1, it enables the ATA_PDIAG/
ATA_BHE/RING_IN pin to be used as a Byte High Enable
pin on a local interface side. Byte High Enable is used to
signify that a PCMCIA host is requesting or sending data
on the high byte bus pins ATA_DATA[15-8] of the local
bus. For ATA_BHE, also see Register 2Fh. When set to 0,
ATA_PDIAG/ATA_BHE/RING_IN is used as a local
bidirectional PDIAG pin. On Power-On Reset, this bit is
set to 0.
Programming Internal Registers
PS012002-1201