XGS Family

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17

SENSOR STATES

After Power−Up and while the RESET_N pin is driven

low, the image sensor enters a RESET state until the

RESET_N signal is de−asserted.

Once the RESET_N pin is driven high, the sensor will

start loading the default configuration, stored in the on−chip

memory, into its configuration registers before it enters the

SLEEP state. While the sensor is in the SLEEP state, the

registers can be programmed using the serial interface. To

exit the SLEEP state and enter STANDBY mode, the

reset_register_reg (R0x3700) needs to be set to 0x001C.

This register upload enables all analog blocks (including the

on−chip PLL) and as soon as the sensor_status_reg

(R0x3706) returns value 0xEB, the sensor is in STANDBY

state.

When in STANDBY mode and upon user intervention the

training patterns or IDLE words can be sent over the video

interface allowing receiver locking. Once the host is ready

to receive image data, the sensor’s sequencer can be enabled.

Depending on the configured operation mode, the sensor

will either wait for user interaction or start grabbing images

autonomously (CAPTURE). Disabling the sequencer

moves the sensor state back to STANDBY. When disabling

the PLL and analog blocks while in STANDBY state, the

state machine will transition back to the SLEEP state.

Asserting the RESET_N pin forces the sensor to enter the

RESET state, regardless of the current state.

The sensor state diagram is shown in Figure 11.

Figure 11. Sensor State Diagram

RESET_N de−asserted −> internal initialization start

R0x3706 = 0xEB?? −> Initialization complete

*

*The sleep mode functionality is not available. Please use the standby mode when the sensor is idle. Technical details on this issue can be

found in the developer guide.

Table 6. TYPICAL TRANSITION TIMES

Sensor State

Transition Time

Description

POWER−DOWN

25 ms

Time required to transition from POWER−DOWN to CAPTURE state.

SLEEP

10 ms

Time required to transition from SLEEP to CAPTURE state.

STANDBY

< 16 line times

Time required to transition from STANDBY to CAPTURE state.

WAIT_ON_TRIGGER

2 line times + Synchroniza-

tion Delay (< 50 ns)

Time required to transition from WAIT_ON_TRIGGER to CAPTURE (upon

trigger action). A minimum delay of one line time will be added.