Jtag/Gspi Header (Jp1); Lock And Data Error Status; Modes Of Operation - Semtech EB-GS2971 User Manual

1.5 JTAG/GSPI Header (JP1)

The GS2971 contains a set of internal status and configuration registers. These registers
are available to the host via the GS2971's GSPI pins. Access to the applicable pins on the
GS2971 is provided using the JTAG/GSPI header.
A GSPI dongle is provided for communication to the GSPI interface. If you have the
EB-GS2971 and an EB-GS2972 connected together, only one GSPI dongle is required,
and can be connected to either of the boards.

1.6 Lock and Data Error Status

LED U12 indicates the lock status of the GS2971, and LED U13 indicates data error. Both
are bi-colour devices. See Table 1-3 below.
Table 1-3: Lock and Data Error Status
LED Green Red
U12 (Lock Status) Locked Unlocked
U13 (Data Error Status) No Error Detected Error Detected

1.7 Modes of Operation

The GS2971 supports four distinct modes of operation that can be set through the DIP
switch or by programming internal registers through the GSPI. These modes are: SMPTE
mode, Data-Through mode, DVB-ASI mode and Standby mode.
The GS2971 can automatically detect the format of the incoming signal when
AUTO/MAN = HIGH. If the format of the incoming signal is not recognized, the GS2971
defaults into SMPTE Bypass mode. Alternatively, the device may be forced into any of
the four modes through the Host Interface (Address 024h).
In SMPTE mode, the GS2971 performs full SMPTE processing, and features a number of
signal integrity checks and measurement capabilities.
In DVB-ASI mode, 8b/10b decoding is applied to the received data stream.
In SMPTE Bypass mode, all forms of SMPTE and DVB-ASI decoding are disabled, and the
device can be used as a simple serial-to-parallel converter without incurring the latency
penalties associated with SMPTE or DVB-ASI mode.
The device can also operate in a lower power Standby mode. In this mode, no signal is
generated at the output.
The DIP switch (SW2) corresponds directly to pins on the GS2971. Refer to the GS2971
Data Sheet for a more detailed explanation of the modes of operation.
EB-GS2971 8 of 22
Evaluation Board User Guide
52169 - 2 June 2012 Proprietary & Confidential