CS8900A
Crystal LAN™ ISA Ethernet Controller
Not in Boundary Scan
Test Mode
TEST switches low (AEN must be low)
ENTER BOUNDARY SCAN:
CS8900A resets, all digital
output pins and bi-directional
pins enter High-Z state,
and AEN becomes shift clock
AEN switches high
AEN switches low
34 cycles
Selected output
goes low
OUTPUT CYCLE
AEN switches high
AEN switches low
50 cycles
Selected input
copied out
to the
EEDataOut
pin
INPUT CYCLE
AEN switches high
AEN switches low
All digital output pins and
bi-directional pins enters
High-Z state
AEN switches high
TEST switches high
EXIT BOUNDARY SCAN:
AEN becomes ISA bus
Address Enable
Figure 32. Boundary Scan Continuity Cycle
CIRRUS LOGIC PRODUCT DATA SHEET
DS271PP3
109
CIRRUS [ CIRRUS LOGIC ]
