ID 683171
Date 7/26/2022
Public

## 17.25.1. Direct Write Reconfiguration

Follow these steps to reconfigure a transceiver setting using a series of Avalon-MM direct writes.
1. Write the logical channel number to the Streamer logical channel register.
2. Write Direct Mode, 2'b01, to the Streamer control and status register mode bits.
3. Write the offset address to the Streamer offset register.
4. Write the offset data to the Streamer data register.
5. Write the Streamer control and status register write bit to 1'b1 to initiate a write of all the data set in the previous steps.
6. Repeat steps 3 through 5 if the offset data length is greater than 1. Increment the offset value by 1 for each additional data record.
7. Read the control and status register busy bit. When the busy bit is deasserted, the operation has completed.

In Steps 3 and 4, you must specify an offset value and offset data. You can determine the values of the offset address and offset data by examining the data records specified in either the channel or PLL MIFs.

Figure 94. Sample MIF

For the sample data record, the length field specifies three data records. The offset value is 0, as indicated by bits 10–0. The offset data are the three subsequent entries. The following example performs a direct write in Streamer mode 1. This example writes the sample MIF into the Streamer module which writes this data to logical channel 0.

### Streamer Mode 1 Reconfiguration

#Setting logical channel 0
write_32 0x38 0x0
#Read the busy bit to determine when the operation completes
#Setting Streamer to mode to 1
write_32 0x3A 4'b0100
#Read the busy bit to determine when the operation completes
#Setting Streamer offset register to the offset address
#In the example record, the first offset address is 0x0
write_32 0x3B 0x0
#Read the busy bit to determine when the operation completes
#Setting data register with the first data record
write_32 0x3C 16'b0010100000100000
#Read the busy bit to determine when the operation completes
#Writing first data to the Streamer
write_32 0x3A 0x5
#Read the busy bit to determine when the operation completes
#Incrementing Streamer offset register offset address
write_32 0x3B 0x1
#Read the busy bit to determine when the operation completes
#Setting data register with the second data record
write_32 0x3C 16'b0010001110110000
#Read the busy bit to determine when the operation completes
#Writing second data to the Streamer
write_32 0x3A 0x5
#Read the busy bit to determine when the operation completes
#Incrementing Streamer offset register offset address
write_32 0x3B 0x2
#Read the busy bit to determine when the operation completes
#Setting data register with the third data record
write_32 0x3C 16'b1000000111010100
#Read the busy bit to determine when the operation completes
#Writing third data record to the Streamer
write_32 0x3A 0x5
#Read the busy bit to determine when the operation completes