Difference between revisions of "Novena/EEPROM"
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Revision as of 02:11, 30 September 2013
Novena has a utility EEPROM that can be used for storing device-specific data. This is optional, and default values will be used if it is blank / not present.
All multi-byte integers are in native host order.
Structure
| Size | Default Value | Description | Result if no EEPROM present |
|---|---|---|---|
| 6 | 'Novena' | Unterminated EEPROM signature | The EEPROM contents will not be used |
| 1 | 1 | Version number of EEPROM structure | The EEPROM contents will not be used |
| 1 | 0 | Reserved | No change |
| 4 | 0 | Device serial number | No change |
| 6 | (Random) | Gigabit MAC address | Random MAC address is generated on each boot |
| 2 | 0 | Feature bitmask | No features are enabled |
Feature bitmask
There is a bitmask field that defines various board features. In this way, a single image can be shipped that supports various components. For example, a router might not have a display, but a laptop would need to have its LCD turned on. A bit is "1" if the feature is present (and needs to be enabled), and "0" if it is not present. Note that some values are mutually-exclusive (e.g. you can only have one kind of LVDS display attached).
| Bit position | Feature |
|---|---|
| 1 | ES8328 Audio Codec |
| 2 | Battery board |
| 3 | Retina LVDS display |
| 4 | (Reserved: Other LVDS display) |
| 5 | mPCIe port |
