Hybrid interface for serial and parallel communication

An apparatus comprising:

• an interface for transmission of data to or reception of data from a second apparatus, wherein the interface includes:
• a first mode for a parallel interface with the second apparatus, the parallel interface including a first plurality of pins for transmitting parallel data to the second apparatus or receiving parallel data from the second apparatus in the first mode, wherein the parallel interface has a first voltage swing, and
• a second mode for a serial interface with the second apparatus, the serial interface including a second plurality of pins for transmitting serial data to the second apparatus or receiving serial data from the second apparatus in the second mode, the first plurality of pins and the second plurality of pins both including an overlapping set of pins, wherein the serial interface has a second voltage swing, the second voltage swing being smaller than the first voltage swing;
• and
• a reference oscillator circuit, wherein for the second mode the reference oscillator circuit is enabled if the reference oscillator circuit is disabled.

A computer-readable medium having stored thereon data representing sequences of instructions that, when executed by a processor, cause the processor to perform operations comprising:

• initializing a first apparatus for transmission of data to or reception of data from a second apparatus, the first apparatus including a reference oscillator circuit;
• enabling an interface for the first apparatus initially in a first mode for a parallel interface with the second apparatus, the parallel interface including a first plurality of pins, wherein the parallel interface has a first voltage swing;
• transmitting parallel data to the second apparatus or receiving parallel data from the second apparatus in the first mode via the first plurality of pins;
• enabling the reference oscillator circuit and enabling the interface of the first apparatus in a second mode for a serial interface with the second apparatus, the serial interface including a second plurality of pins, the first plurality of pins and the second plurality of pins both including an overlapping set of pins, wherein the serial interface has a second voltage swing, the second voltage swing being smaller than the first voltage swing;
• and
• transmitting serial data to the second apparatus or receiving serial data from the second apparatus in the second mode via the second plurality of pins.