Product specifications

VT8237R Data Sheet
Revision 2.06 December 15, 2004 -10- Pin Descriptions
PIN DESCRIPTIONS
V-Link Pin Descriptions
V-Link Interface
Signal Name Pin # I/O Signal Description
VD[15:0]
(see
pin
list)
IO Data Bus. All bits 15-0 are implemented for use with VIA north bridge chips which
support this capability (if not, only bits 7-0 are used). VD[7:0] are also used to send strap
information to the chipset north bridge (see strap table below for details). The specific
interpretation of these straps is north bridge chip design dependent.
VPAR
F24 IO Parity. If the VPAR function is implemented in a compatible manner on the north bridge,
this pin should be connected to the north bridge VPAR pin (KT400 / KM400 / KN400,
PT400, PT600). If VPAR is not implemented in the north bridge chip or is incompatible
with the VT8237R (4x V-Link north bridges) connect this pin to an 8.2K pullup to 2.5V
(Pro266, Pro266T, KT266, KT266A, KT333, P4X266, PN266, KN266, KM266, P4M266,
P4N266). See app note AN222 for details.
VBE#
G24 IO Byte Enable. Connect to same named pin on north bridge.
VCLK
L22 I V-Link Clock. 66 MHz. Supplied by clock generator.
UPCMD
K23 O Command from Client-to-Host. Connect to same named pin on north bridge.
DNCMD
K25 I Command from Host-to-Client. Connect to same named pin on north bridge.
UPSTB
J26 O Strobe from Client-to-Host. Connect to same named pin on north bridge.
UPSTB#
J24 O Complement Strobe from Client-to-Host. Connect to same named pin on north bridge.
DNSTB
H26 I Strobe from Host-to-Client. Connect to same named pin on north bridge.
DNSTB#
H24 I Complement Strobe from Host-to-Client. Connect to same named pin on north bridge.