
168
Am79C965A
ECS is set to ZERO by H_RESET
and is unaffected by S_RESET or
STOP.
1
ESK
EEPROM Serial Clock. This bit and
the EDI/EDO bit are used to control
host access to the EEPROM. Values
programmed to this bit are placed
onto the EESK pin at the rising edge
of the next BCLK following bit
programming, except when the
PREAD bit is set to ONE or the EEN
bit is set to ZERO. If both the ESK bit
and the EDI/EDO bit values are
changed during one BCR19 write
operation, while EEN = 1, then setup
and hold times of the EEDI pin value
with respect to the EESK signal
edge are not guaranteed.
Table 52. EEPROM Enable
ESK has no effect on the EESK pin
unless the PREAD bit is set to
ZERO and the EEN bit is set to
ONE.
ESK is reset to ONE by H_RESET
and is unaffected by S_RESET or
STOP.
0
EDI/EDO EEPROM Data In/EEPROM Data
Out. Data that is written to this bit will
appear on the EEDI output of the
microwire interface, except when the
PREAD bit is set to ONE or the EEN
bit is set to ZERO. Data that is read
from this bit reflects the value of the
EEDO input of the microwire
interface.
EDI/EDO has no effect on the EEDI
pin unless the PREAD bit is set to
ZERO and the EEN bit is set to
ONE.
EDI/EDO is reset to ZERO by
H_RESET and is unaffected by
S_RESET or STOP.
BCR20: Software Style
Bit
Name
Description
This register is an alias of the lo-
cation CSR58. Accesses to/from
this register are equivalent to
accesses to CSR58.
31-10 RES
Reserved locations. Written as
ZEROs and read as undefined.
9
CSRPCNET CSR PCnet-ISA configuration bit.
When set, this bit indicates that the
PCnet-32 controller register bits of
CSR4 and CSR3 will map directly to
the CSR4 and CSR3 bits of the
PCnet-ISA (Am79C960) device.
When cleared, this bit indicates that
PCnet-32 controller register bits of
CSR4 and CSR3 will map directly to
the CSR4 and CSR3 bits of the
ILACC (Am79C900) device.
The
determined by the PCnet-32 con-
troller. CSRPCNET is read only by
the host.
value
of
CSRPCNET
is
The PCnet-32 controller uses the
setting of the Software Style register
(BCR20[7:0]) to determine the value
for this bit.
CSRPCNET is set by H_RESET
and is not affected by S_RESET or
STOP.
8
SSIZE32 Software Size 32 bits. When set, this
bit indicates that the PCnet-32
controller utilizes AMD79C900
(ILACC) software structures. In
particular, Initialization Block and
Transmit and Receive descriptor bit
maps are affected. When cleared,
this bit indicates that the PCnet-32
controller utilizes AMD PCnet-ISA
software structures.
Note:
Regardless of the setting of
SSIZE32, the Initialization Block
Reset
Pin
PREAD or
Auto Read in
Progress
EEN
EECS
SHFBUSY
EESK
EEDI
High
X
X
0
1
Z
Z
Low
1
X
Active
1
Active
Active
Low
0
1
From ECS
Bit of BCR19
From EBUSY
Bit of BCR19
From ESK Bit
of BCR19
From EEDI Bit
of BCR19
Low
0
0
0
PVALID
LED1
LNKST