Figure 1Figure 2

123456

IRQ0

INTD

– –

–

Start Frame

RR

R

TT

T

SS

PCLK

POLLMODE

PCI950

IRQSER

DRIVE

Stop Frame

RT

(see Note 7)

PCI950

IRQ0

INTD

– – –

Start Frame

RR

R

TT

T

SS

PCI950

Stop Frame

RT

(see Note 8)

PCI950

Clocks

Legend:

R = Recovery

S = Sample

T = Turnaround

17

NOTES:

7. When the POLLMODE input level changes before the rising edge of the start frame, then the stop-frame width in the current IRQSER cycle reflects the change in mode.

8. Any change in the POLLMODE input level after the start frame is complete is reflected in the next IRQSER cycle.

Figure 3. POLLMODE Level Change During an IRQSER Cycle