IRCC2.0 SMSC Corporation, IRCC2.0 Datasheet - Page 80

• Manufacturer Part Number: IRCC2.0
• Description: Infrared Communications Controller
• Manufacturer: SMSC Corporation

IOCHRDY Timer
The 10Fs IOCHRDY Timer is initialized when
IOCHRDY is active. The timer count sequence
is activated when IOCHRDY goes inactive.
IOCHRDY becomes active before the 10Fs time-
Zero Wait State Support
nSRDY
nSRDY can be driven by the IrCC 2.0 to indicate
that an access cycle shorter than the standard
I/O cycle can be executed. Note: The names
nSRDY & nNOWS can be used interchangeably.
nSRDY is enabled by the No Wait bit in SCE
IOCHRDY Time-out
FIFO Not Empty
FIFO Not Empty
FIGURE 48 - VALID I/O READ READY CYCLE
String Move
String Move
FIGURE 49 - IOCHRDY 10FS TIME-OUT
IOCHRDY
IOCHRDY
AEN
IOR
AEN
IOR
If
80
Timer
out has elapsed, the timer is stopped and the
count is re-initialized. If IOCHRDY is still inactive
when the 10Fs time-out occurs, the timer stops,
the time-out error bit is set, IOCHRDY is re-
asserted, and the string move bit is reset (Figure
49).
Configuration Register B. When No Wait is one,
nSRDY goes active following the trailing edge of
the ISA I/O command and inactive following the
rising edge (Figure 50). nSRDY is suppressed
during DMA & refresh cycles, i.e. when AEN is
active, or when IOCHRDY is inactive. Zero Wait
State support is only available when the SCE is
enabled.
Start
24ns (max)
10us
IOCHRDY
10us (max)
Error