Interrupt ed structure -4, Figure 12-4 – Freescale Semiconductor MPC5200B User Manual

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MPC5200B Users Guide, Rev. 1

12-4

Freescale Semiconductor

Host Controller Interface

Figure 12-4. Interrupt ED Structure

Figure 12-5

shows a sample interrupt endpoint schedule. The schedule shows:

two endpoint descriptors at a 1ms poll interval

two endpoint descriptors at a 2ms poll interval

one endpoint descriptor at a 4ms poll interval

two endpoint descriptors at an 8ms poll interval

two endpoint descriptors at a 16ms poll interval

two endpoint descriptors at a 32ms poll interval.

NOTE

Unused interrupt endpoint placeholders are bypassed and the link is connected to the next available
endpoint in the hierarchy.

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Interrupt

Endpoint

Descriptor

Placeholder

Endpoint Poll Interval (ms)

Interrupt

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