The VMK180 evaluation board implements the ANSI/VITA 57.4 IPMI support functionality. The power control of the VADJ_FMC power rail is managed by the ZU4 U125 System Controller. This rail powers both FMCP HSPC J51 and J53 VADJ pins, as well as the XCVM1802 U1 VCCO on the FMCP interface banks 706, 707, and 708. The valid values of the VADJ_FMC rail are 0, 1.2V, or 1.5V. At power on, the System Controller detects if an FMC module is installed on J51 or J53. The following sequence of actions then take place:
- If no card is attached to a FMCP connector, the VADJ_FMC voltage is set to 1.5V
- When an FMC card is attached, its IIC EEPROM is read to find a VADJ voltage supported by both the VMK180 board and the FMC module, within the available choices of 0, 1.2V, or 1.5V
- If no valid information is found in an attached FMC card IIC EEPROM, the VADJ_FMC rail is set to 0.0V
The System Controller user interface allows the FMC IPMI routine to be overridden and an explicit value can be set for the VADJ_FMC rail. The override mode is useful for FMC mezzanine cards that do not contain valid IPMI EPROM data defined by the ANSI/VITA 57.4 specification.