user manual

Software Developer’s Manual 271
Register Descriptions
13.4.7.1.17 Extended PHY Specific Control Register 1
1
EPSCON1 (20d; R/W)
1. Extended PHY Specific Control Register - EPSCON for the 82544GC/EI only.
Table 13-39. Extended PHY Specific Control 1 Bit Description
1
Field Bit(s) Description Mode HW Rst SW Rst
Reserved 1:0 00b R/W 00b Retain
Reserved 3 0b R/W 0b 0
Reserved 6:4
Reserved. Should be set to 0b.
Changes to this bit are disruptive to the
normal operation; any change to this
register must be followed by software
reset to take effect.
R/W 110b Update
Reserved 7
Reserved. Should be set to 0b.
Changes to this bit are disruptive to the
normal operation; any change to this
register must be followed by software
reset to take effect.
R/W 0b Update
Slave downshift
counter
9:8
00b = disable. (10/100 downshift)
01b = 1x.
10b = 2x.
11b = 3x.
Changes to this bit are disruptive to the
normal operation; any change to this
register must be followed by software
reset to take effect.
Bits 11:10 have no effect unless bits 1:0
are set to their default values.
R/W 01b Update
Master downshift
counter
11:10
00b = 1x.
01b = 2x.
10b = 3x.
11b = 4x.
Number of times that the PHY attempts
to achieve gigabit link before
downshifting to the next speed in Master
Mode.
Changes to this bit are disruptive to the
normal operation; any change to this
register must be followed by software
reset to take effect.
Bits 11:10 have no effect unless bits 1:0
are set to their default values.
R/W 11b Update
Reserved 12 Reserved. Should be set to 0b. R/W 0b 0b
Reserved 13 Reserved. Should be set to 0b. R/W 0b 0b
Reserved 14 Reserved. Should be set to 0b. R/W 0b 0b
Reserved 15 Reserved. Should be set to 0b. R/W 0b 0b