CPRI™ – TDM FIC EVM board

CPRI™ – TDM FIC EVM board

The CPRI™ – TDM FIC EVM board allows a Time-Division Multiplexing (TDM), as well as Time-Division De-Multiplexing CPRI version 2.1 solution from a radio equipment controller to radio equipment(s). The advantage of using this platform is its possibilities of connecting to the embedded processor for data processing through CPRI links directly. The embedded processor is configured as the master, whereas the CPRI™ – TDM FIC is the slave.

CPRI™ – TDM FIC to TSW3003

For outbound data transfers, I and Q data coming from the embedded processor are firstly multiplexed so that these data can be sent simultaneously at the DAC side. Regarding the board connection, the TDM J100 from the CPRI™ – TDM FIC EVM board is connected to the TSW3003 Port A:

J100 of TDM	Port A of TSW3003
1-33	1-33

Next, the QFLAG of the DAC is needed to identify the channel B. Therefore, it is connected to pin 3 – J104 of TDM.

J104 of TDM	Port B of TSW3003	Signal name
3	33	QFLAG

View of board connection CPRI™ – TDM FIC to TSW3003

ADS5231 to CPRI™ – TDM FIC

The CPRI™ – TDM FIC can be used with the two ADCs since it allows data fusion from these two ports to a single port. Data is then transferred within short time segments. Digital converted data from the ADC is received at TDM CPRI board via connectors J102 and J103. However, only 8 MSBs from each output of ADC is present on the CPRI™ – TDM FIC. From here, data is sent to FIC by passing through the FPGA. The FPGA acts as a buffer and doesn\’t modify the data received from ADC. Data from ADC A is present at TDM Port 0, while data from ADC B is found at TDM Port 1 in 16 bits. Since data received is in 8 bits, only 8 LSBs are present within this data buffer.

CPRI™ – TDM FIC configuration

The configuration is achievable owing to the I²C interface. Moreover, the CPRI™ – TDM FIC EVM board provides an interface that allows user to configure the FIC, performing a register check as well as to monitor the uplink/downlink data that arrive in the FPGA.

Steps to be followed for FIC configuration:

1. Connect the USB-I²C adaptor from the USB port on the machine to the Aardvark I²C interface on the CPRI™ - TDM FIC platform (J8).

1. Execute IDT sRIO Device Wizard Rev 3.6 (IDT_sRIO_Device_Wizard.exe). Once connected, three devices will be detected by the I²C. Define I²C ID number which is associated to the FIC for configuration (I2C ID \# &h30 80HFC1001 0).

1. Open TITXparaleRxparalell.trm file containing registers configuration of the FIC. The contents of each register can be viewed in the left section of the interface.
2. Make sure that the ID number corresponds to the one of the FIC used. Modify the ID number if necessary.

1. Check the switch SW3 setting on the CPRI™ - TDM FIC board. Make sure that it is in the loopback mode configuration "001111001111" by verifying in the GUI (EVB  TDM EVB  Main Manual).

1. Program the FIC by clicking at the "Run List" button.

1. To make sure that the FIC is well configured, verify the registers values (FIC  80HFC1001  List of registers).

Data in the CPRI™ – TDM FIC can be observed in the TDM Evaluation Board (EVB  TDM EVB  Main Manual).