- The HOST_IRQ signal is provided to indicated when
the system has completed auto-initialization.
- While reset is applied, HOST_IRQ is tri-stated
(an external pullup resistor pulls the line
high).
- HOST_IRQ remains tri-stated (pulled high
externally) until the boot process completes.
While the signal is pulled high, this indicates
that the controller is performing boot-up and
auto-initialization.
- As soon as possible after the controller
boots-up, the controller drives HOST_IRQ to a
logic high state to indicate that the controller
is continuing to perform auto-initialization (no
real state changes occur on the external
signal).
- The software sets HOST_IRQ to a logic low state
at the completion of the auto-initialization
process. At the falling edge of the signal, the
initialization is complete.
- The DLPC1438 controller is ready to receive
commands through I2C or accept video
over the video interface only after
auto-initialization is complete.
- The controller initialization typically completes
(HOST_IRQ goes low) within 500 ms of RESETZ being
asserted. However, this time may vary depending on
the software version and the contents of the user
configurable auto initialization file.