National Semiconductor SD303EVK User Manual page 4

¯¯¯¯
RSTI
¯¯¯¯ push button switch controls RSTI
The RSTI
driver to its default register settings. The RSTI
the cable driver is held in reset (RSTI
toggle reset: once to put the device in reset mode (RSTI
with the default register settings.
¯¯¯¯¯
RSTO
¯¯¯¯¯ LED shows the state of RSTO
The RSTO
reset output used when daisy chaining multiple cable drivers on the same SMBus. After writing a new device
address to register 00h (the ID register), the RSTO
high until the device is reset with RSTI
Termination Faults (TFxx)
The Termination Fault LEDs show the state of the Termination Faults on the cable driver outputs. The Termination
Fault LEDs are Green to indicate proper termination, Red to indicate improper or missing termination, and off to
indicate the Termination Faults are not valid under the current cable driver conditions.
The cable driver must be enabled and must have a valid input signal in order to properly detect cable termination
on the output. If no signal is detected and the LOS
TF0P, and TF0N for the LMH0307) cannot determine the state of the output termination and the LEDs will be off.
When a valid input signal is applied, the Termination Fault detectors will show the correct state of their termination.
If the cable driver is disabled or if the output channel is powered down, the Termination Fault LEDs will be off.
¯¯¯¯
LOS
¯¯¯¯ LED shows the status of the input signal detector. The LOS
The LOS
¯¯¯¯ = 1), and Red when no signal is detected (LOS
signal (LOS
¯¯¯¯ detection is disabled as well and the LOS
the LOS
¯¯¯¯ LED is Red, then the Termination Fault detection does not function and the TFxx LEDs are forced off.
LOS
With the LOSEN register bit (bit 4 of register 05h) set, the LOS
disabled. In this mode, LOS
cable driver will power down but keep the LOS
signal is detected. (While in this mode, disabling the device by pushing the ENABLE switch will still power down
the device completely, including powering down Termination Fault and LOS
LEDs and Push Button Switches Summary
Table 2 shows a summary of the LEDs provided to assist the user in determining the configuration of the board,
and Table 3 shows a summary of the push button switches provided to allow control of the board functions.
SD303/SD307 EVK User Guide
Rev 1.2
¯¯¯¯ , and the RSTI
¯¯¯¯ LED is Green during normal operation (RSTI
¯¯¯¯ = 0). To reset the device, the RSTI
¯¯¯¯¯ . The RSTO
¯¯¯¯¯ LED changes to Green to indicate RSTO
¯¯¯¯ .
¯¯¯¯ LED is Red, then the Termination Fault detectors (TF1P, TF1N,
¯¯¯¯ LED will be Red to indicate no signal can be detected. If the
¯¯¯¯ is combined with the ENABLE functionality, and if the input signal is removed then the
¯¯¯¯ detection running. The device will power back on once an input
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¯¯¯¯ LED shows its state. RSTI
¯¯¯¯ switch must be pushed twice to fully
¯¯¯¯ = 0), and again to resume normal operation (RSTI
¯¯¯¯¯ LED is normally Red to indicate RSTO
¯¯¯¯ LED is Green to indicate a valid input
¯¯¯¯ = 0). When the cable driver is disabled (ENABLE = 0),
¯¯¯¯ detection may still function while the cable driver is
¯¯¯¯ detection).
¯¯¯¯ is used to reset the cable
¯¯¯¯ = 1), and Red when
¯¯¯¯ = 1)
¯¯¯¯¯ = 0. RSTO ¯¯¯¯¯ is the
¯¯¯¯¯ = 1. RSTO ¯¯¯¯¯ remains