W89C940 Datasheet, PDF (15/61 Pages) Winbond – ELANC-PCI (TWISTED-PAIR ETHER-LAN CONTROLLER WITH PCI INTERFACE)

W89C940
CONFIGURATION PROGRAMMING FUNCTION
ELANC-PCI Mode Configuration Registers
MCR
A mode configuration register(MCR) is used to program the operation mode of the ELANC-PCI. The address is
page 0, 0AH. MCR can be updated by software. Reading this register is the same as reading a register in the
SLCT core coprocessor. Writing to these registers is done by first reading the register to be written to and then
using a slave write operation to update the configurations.
The content of MCR is as following table:
BIT SYMBOL
DESCRIPTION
0
PHY0 Physical Layer Interface:
1
PHY1 These two bits select the type of physical interface which the ELANC-PCI
attached on. Both the thin Ehternet and thick Ethernet type use the AUI of
ELANC-PCI as the input/output interface. The other two UTP types,then, use
the TPI of ELANC-PCI as the input/output interface. The output and input pins
of AUI or TPI are idle, when the corresponding type is not selected.
PHY1 PHY0 Physical Interface Type
0 0 UTP (with 10BASE-T compatible receive squelch level)
0 1 Thin Ethernet
1 0 Thick Ethernet (AUI port)
1 1 UTP (with reduced receive squelch level)
2 GDLNK Good Link Status:
A read operation on this bit will get the link test status. A "1" indicate that it is
link good and a "0" is link fail.
The GDLNK do not imply any information if the PHY0 and PHY1 is
programmed as Thin or Thick Ethernet.
3 LNKEN Link Test Pulse enable:
The network media auto switching function, link integrity test function and the
link test pulse generation function will be enabled when LNKEN = "0".
Otherwise, all of these functions will be disabled when LNKEN = "1".
4
SHLS _{SRAM High/Low Speed Select:}
High speed SRAM with 20nsec access time is selected if SHLS =1. Low
speed SRAM with 70nsec access time is selected if SHLS =0.
5
BPS0 BOOT PROM Size:
6
BPS1 The size of the BOOT PROM is selected by BPS0, BPS1, and BPS2.
7
BPS2 BPS2 BPS1 BPS0
SIZE
00X
No boot PROM
010
8K
011
16K
100
32K
101
64K
110
128K
111
256K
15