Visible to Intel only — GUID: iga1401400499396
Ixiasoft
Visible to Intel only — GUID: iga1401400499396
Ixiasoft
39.3.1. Functional Description
You can configure the width of the output data signal to either 32-bit or 40-bit when instantiating the core. The chosen data width is not configurable during run time.
You can configure this core to output 8-bit or 10-bit wide symbols. By default, the core generates 4 symbols per beat, which outputs 32-bit or 40-bit wide data to the Avalon® -ST interfaces, respectively. The core’s data format endianness is the most significant symbol first within a beat and the most significant bit first within a symbol. For example, when you configure the output data to 32-bit, bit 31 is the first data bit, followed by bit 30, and so forth. This interface’s endianness may change in future versions of the core.
If you configure the width of the output data to 32-bit, the core inputs four 8-bit wide symbols per beat. To achieve an 8-bit and 16-bit data width, you can use the Avalon® -ST Data Format Adapter component to convert 4 symbols per beat to 1 or 2 symbols per beat.
Similarly, if you configure the width of the output data to 40-bit, the core inputs four 10-bit wide symbols per beat. The 10-bit and 20-bit input can be achieved by switching from 4 symbols per beat to 1 and 2 symbols per beat.
Control and Status Interface
The control and status interface is an Avalon® -MM agent that allows you to enable or disable the pattern checking. This interface also provides the run-time ability to choose the data pattern and read the status signals.
Input Interface
The input interface is a parallel Avalon® -ST interface. You can configure the data width at this interface to suit your requirements.
Supported Data Patterns
The following data patterns are supported in the following manner, per beat. When the core is disabled or in idle state, the default pattern generated on the data output is 0×5555 (for 32-bit data width) or 0×55555 (for 40-bit data width).
Pattern | 32-bit | 40-bit |
---|---|---|
PRBS-7 | PRBS in parallel | PRBS in parallel |
PRBS-15 | PRBS in parallel | PRBS in parallel |
PRBS-23 | PRBS in parallel | PRBS in parallel |
PRBS-31 | PRBS in parallel | PRBS in parallel |
High Frequency | 10101010 x 4 | 1010101010 x 4 |
Low Frequency | 11110000 x 4 | 1111100000 x 4 |
Lock
The lock bit in the status register is asserted when 40 consecutive bits of correct data are received. The lock bit is deasserted and the receiver loses the lock when 40 consecutive bits of incorrect data are received.
Bit and Error Counters
The core has two 64-bit internal counters to keep track of the number of bits and number of error bits received. A snapshot has to be executed to update the NumBits and NumErrors registers with the current value from the internal counters.
A counter reset can be executed to reset both the registers and internal counters. If the counters are not being reset and the core is enabled, the internal counters continues the increment base on their current value.
The internal counters only start to increment after a lock has been acquired.