XR17V252 Datasheet, PDF (5/69 Pages) Exar Corporation – 66 MHZ PCI BUS DUAL UART WITH POWER MANAGEMENT SUPPORT

REV. 1.0.1
PIN DESCRIPTIONS
XR17V252
66 MHZ PCI BUS DUAL UART WITH POWER MANAGEMENT SUPPORT
NAME
ENIR
EN485#
PME#
PIN #
74
65
79
TYPE
DESCRIPTION
I ^{Global Infrared mode enable (active high). This pin is sampled during power}
up, following a hardware reset (RST#) or soft-reset (register RESET). It can
be used to start up both UARTs in the infrared mode. The sampled logic state
is transferred to MCR bit-6 in the UART. Software can override this pin there-
after and enable or disable it.
I ^{Global AutoRS485 half-duplex direction control enable (active low). During}
power up or reset, this pin is sampled and if it is a logic high, both UARTs are
set for Auto RS485 Mode. Also, the Auto RS485 bit, FCTR[5], is set in both
channels. Software can override this pin thereafter and enable or disable it.
OD Power Management Event signal. While in D3_hot state, if the PME_Enable bit
in the Power Management Control/Status Register is set, the V252 asserts
the PME# upon receiving a new character or upon change of state of modem
inputs on any channel.
VCC
54, 80, 10, 22, PWR Power supply for the UART core logic and PCI bus I/O - 3.3V only. The V252
32, 43, 89, 100
is PCI 3.0 signalling compliant at 3.3V operation. The non-PCI inputs (except
XTAL1) are 5V tolerant. This includes all the serial (modem) inputs.
GND
1, 11, 23, 33, PWR Power supply common, ground.
44, 53, 78, 88
NC
63, 64
No Connection.
NOTE: Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
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