Datasheet

3−6
ZVSTAT
PCI1510
ZVSEL0
Figure 3−5. Zoomed Video Switching Application
Figure 3−5 illustrates an implementation using standard three-state bus drivers with active-low output enables.
ZVSEL0
is an active-low output indicating that the socket ZV mode is enabled.
3.5.4 Standardized Zoomed-Video Register Model
The standardized zoomed-video register model is defined for the purpose of standardizing the ZV port control for PC
Card controllers across the industry. The following list summarizes the standardized zoomed-video register model
changes to the existing PC Card register set.
• Socket present state register (CardBus socket address + 08h, see Section 6.3)
Bit 27 (ZVSUPPORT) has been added. The platform BIOS can set this bit via the socket force event register
(CardBus socket address + 0Ch, see Section 6.4) to define whether zoomed video is supported on the
socket by the platform.
• Socket force event register (CardBus socket address + 0Ch, see Section 6.4)
Bit 27 (FZVSUPPORT) has been added. The platform BIOS can use this bit to set the ZVSUPPORT bit in
the socket present state register (CardBus socket address + 08h, see Section 6.3) to define whether
zoomed video is supported on the socket by the platform.
• Socket control register (CardBus socket address +10h, see Section 6.5)
Bit 11 (ZV_ACTIVITY) has been added. This bit is set when zoomed video is enabled for the PC Card socket.
Bit 10 (STDZVREG) has been added. This bit defines whether the PC Card controller supports the
standardized zoomed-video register model.
Bit 9 (ZVEN) is provided for software to enable or disable zoomed video.
If the STDZVEN bit (bit 0) in the diagnostic register (PCI offset 93h, see Section 4.34) is 1b, then the standardized
zoomed video register model is disabled. For backward compatibility, even if the STDZVEN bit is 0b (enabled), the
controller allows software to access zoomed video through the legacy address in the card control register (PCI offset
91h, see Section 4.32), or through the new register model in the socket control register (CardBus socket address +
10h, see Section 6.5).
3.5.4.1 Zoomed-Video Card Insertion and Configuration Procedure
1. A zoomed-video PC Card is inserted into an empty slot.
2. The card is detected and interrogated appropriately.