Instruction Manual

DS271F5 127
CS8900A
Crystal LAN™ Ethernet Controller
CIRRUS LOGIC PRODUCT DATASHEET
SWITCHING CHARACTERISTICS (Continued)
Parameter Symbol Min Typ Max Unit
DMA Read
DMACKx active to IOR
active t
DMAR1
60 - - ns
AEN active to IOR
active t
DMAR2
10 - - ns
IOR
active to Data Valid t
DMAR3
--135ns
IOR
inactive to SD 3-state t
DMAR4
-30-ns
IOR
n-1 high to DMARQx inactive t
DMAR5
- - 20 ns
DMACKx
, AEN hold after IOR high t
DMAR6
20 ns
16-Bit I/O Write
Address, AEN, SBHE
valid to IOCS16 low t
IOW1
- - 35 ns
Address, AEN, SBHE
valid to IOW low t
IOW2
20 - - ns
IOW
pulse width t
IOW3
110 - - ns
SD hold after IOW
high t
IOW4
0--ns
IOW
low to SD valid t
IOW5
- - 10 ns
IOW
inactive to active t
IOW6
35 - - ns
Address hold after IOW
high t
IOW7
0--ns
DIRECTION:
IN or OUT of chip
SD[15:0]
OUT
IOR
DMARQx
OUT
IN
DMACKx IN
AEN
IN
t
DMA1
IOR
n
IOR
n-1
t
DMA2
Valid
Data
Valid
Data
Valid
Data
t
DMA3
t
DMA5
t
DMA4
t
DMA6
Figure 53. 16-Bit DMA Read
Figure 54. 16-Bit I/O Write
SA [15:0],
AEN, SBHE
Valid Address
IOCS16
IN
DIRECTION:
IN or OUT of chip
IOW
SD [15:0] Valid Data In
OUT
IN
IN
t
IOW1
t
IOW2
t
IOW3
t
IOW4
t
IOW5
t
IOW6
t
IOW7