Measuring feedthrough
G Mode Measurement Value (PHY Revision 2 or greater)
The G Mode Measurement value is constructed as follows:
Mask |
Contents |
0x8000 |
Set if BFL_EXTLNA is set in Board Flags and the PHY Revision is greater than 6 |
0x7000 |
Passed in LNA value |
0x0F00 |
Passed in PGA value |
0x0010 |
Always set |
0x00E0 |
Passed in TRSW RX value |
0x0003 |
Bandwidth Flags |
Bandwidth Flags
Value |
Usage |
0x0001 |
Low Pass Filter |
0x0002 |
Low Bandwidth (when set) / High Bandwidth (when unset) |
Non G Mode
Mask |
Usage |
0x8000 |
Low Pass Filter |
0xEFA0 |
Always set |
0x0020 |
Low Bandwidth (when set) / High Bandwidth (when unset) |
0x000F |
Passed in PGA value |
Measuring
- If the PHY Revision is 2 or greater:
Write 0xE300 to PHY register 0x15
Write the constructed value to the extended G PHY register 0x12
- Delay 10 microseconds
Write the constructed value ORed with 2 to the extended G PHY register 0x12
- Delay 10 microseconds
Write the constructed value ORed with 3 to the extended G PHY register 0x12
- Delay 10 microseconds
Write 0xF300 to PHY register 0x15
- Otherwise:
Write the passed in PGA value ORed with 0xEFA0 to PHY register 0x15
- Delay 10 microseconds
Write the passed in PGA value ORed with 0xEFE0 to PHY register 0x15
- Delay 10 microseconds
Write the passed in PGA value ORed with 0xFFE0 to PHY register 0x15
- Delay 21 microseconds
Current feed-through value is available in PHY register 0x2D