The FMC-BB-4DA includes a 128 Kbit IIC EEPROM. This device is non-volatile, retaining its data indefinitely even when power is removed. The FPGA must act as the IIC master to read and write data in the EEPROM. For details of the EEPROM IIC requirements and other specs, refer to the device datasheet (Numonyx M25P128).

The write protect pin on the EEPROM is disabled. As a result the full EEPROM is readable and writable from user applications.

The w3_iic_eeprom core is available for reading and writing the EEPROM from user code.

The IIC EEPROM clock and data lines are tied to the dedicated IIC pins on the FMC header, labeled SDA and SCL in the FMC spec. The EEPROM is powered by the FMC 3P3VAUX FMC power pins (nominally 3.3v; the 24AA128 works with VCC in 1.7-5.5v). The IIC clock and data signals also operate at 3P3VAUX, per the FMC spec. FMC carriers which cannot use 3.3v IO (like WARP v3) must implement level shifting for the IIC lines on the carrier board.

EEPROM Defaults

During manufacturing some board-specific values are written to the top few bytes of the EEPROM. The EEPROM driver provides functions for reading these values in your applications.

Please note the EEPROM does not implement any write protection. It is possible to overwrite these values from user code. We recommend you use the lowest addresses (i.e. starting at byte 0) for any application-specific EEPROM values to avoid overwriting the defaults described below.

The default EEPROM contents are:

  • Tx DC offset calibration: DCO values (16-bit value per I/Q per RF interface) calibrated during manufacturing that can be applied at run-time to minimize the effects of LO leakage in transmitted signals
  • Board serial number: the numeric part of the FMC-BB-4DA board serial number (the last five digits of the FMC-x-NNNNN label), stored as 24-bit value
Byte Addr Value
16364 Reserved
16365 Reserved
16366 Reserved
16367 Reserved
16368 Reserved
16369 Reserved
16370 Reserved
16371 Reserved
16372 Board Serial Number Byte 0 (LSB)
16373 Board Serial Number Byte 1
16374 Board Serial Number Byte 2 (MSB)
16375 Reserved
16376 Reserved
16377 Reserved
16378 Reserved
16379 Reserved
16380 Reserved
16381 Reserved
16382 Reserved
16383 Reserved

Note: the assignment of addresses for the board serial number matches those for the WARP v3 on-board EEPROM, hence the seemingly arbitrary blocks of reserved bytes.

Last modified 11 years ago Last modified on Feb 18, 2013, 11:00:02 PM