DSP56362AD datasheet(29/168 Pages) MOTOROLA

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Signal/Connection Descriptions

Serial Host Interface

MOTOROLA

DSP56362 Advance Information

1-21

HREQ

Input or

Output

Tri-stated

Host Request—This signal is an active low

Schmitt-trigger input when configured for the

master mode but an active low output when

configured for the slave mode.

When configured for the slave mode, HREQ is

asserted to indicate that the SHI is ready for the

next data word transfer and deasserted at the first

clock pulse of the new data word transfer. When

configured for the master mode, HREQ is an input.

When asserted by the external slave device, it will

trigger the start of the data word transfer by the

master. After finishing the data word transfer, the

master will await the next assertion of HREQ to

proceed to the next transfer.

This signal is tri-stated during hardware, software,

personal reset, or when the HREQ1–HREQ0 bits in

the HCSR are cleared. There is no need for

external pull-up in this state.

This input is 5 V tolerant.

Table 1-10 Serial Host Interface Signals (Continued)

Signal Name

Signal Type

State

during

Reset

Signal Description

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

DSP56362AD Datasheet(PDF) 29 Page - Motorola, Inc