Neuromodulation therapy with custom instruction set architecture for a stimulation engine system

A method of operating an implantable medical device (IMD) for providing stimulation therapy to a patient, the IMD including one or more stimulation engines (SEs) operatively coupled to at least one implantable lead having a plurality of electrodes positioned proximate to a tissue of the patient, the method comprising:

• generating, by a first processor of the IMD operative with a first clock frequency, a set of pulse definitions and a set of timing definitions corresponding to a therapy program selection received from an external device responsive to a user input thereat;
• storing the respective sets of pulse definitions and timing definitions in a storage area;
• generating, by the first processor, a sequence of assembly-language like (ALL) instructions for execution by a second processor of the IMD operative with a second clock frequency that is lower than the first clock frequency, the second processor configured to control the one or more SEs for generating one or more pulse waveforms;
• and
• executing at least a portion of the ALL instructions by the second processor for causing the one or more SEs to generate a particular sequence of therapy pulses according to the therapy program selection based on respective combinations of pulse definitions and timing definitions applied over a time base in accordance with the executed ALL instructions.