CS8900A
Crystal LAN™ Ethernet Controller
8). To exit SW Suspend, the host must write to Any hardware reset takes the chip out of any
the CS8900A’s assigned I/O space (the Write sleep mode.
is only used to wake the CS8900A, the Write
Table 9 summarizes the operation of the three
itself is ignored). Upon exit, the CS8900A per-
low-power modes.
forms a complete reset, and then goes through
a normal initialization procedure.
CS8900A Configuration
HWStandbyE HWSleepE SWSuspend
(Pin 77) (SelfCTL, Bit A) (SelfCTL, Bit 9) (SelfCTL, Bit 8) Link Activity
CS8900A Operation
SLEEP
Low
1
1
N/A
Not Present HW Standby mode: 10BASE-T
receiver listens for link activity
Low
Low
1
0
1
1
1
N/A
N/A
0
Present
N/A
HW Standby mode: LANLED low
HW Suspend mode
Low to
High
N/A
N/A
CS8900A resets and goes through
initialization
High
High
Low
Low
N/A
N/A
N/A
N/A
N/A
N/A
0
0
N/A
N/A
N/A
N/A
Not in low-power mode
SW Suspend mode
SW Suspend mode
Not in low-power mode
1
0
0
Notes: 1. Both HW and HW Suspend take precedence over SW Suspend.
Table 9. Low-Power Mode Operation
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