B. RAM Test
This performs a test of the systems host processor RAM. This is the RAM that gets used for user interface and MIDI, unlike the DRAM which stores audio data. The RAM in the JamMan is considered "volitile" so it doesn't remember any settings when the system is power cycled.
If the test fails, the letter "B" is displayed on the JamMan.
C. WCS Test
This performs a test of the Lexichips DSP program memory space. This is the RAM memory that holds the DSP portion of the JamMan code.
If the test fails, the letter "C" is displayed on the JamMan.
E. Interrupt Test
This checks the "interrupt" circuitry on the JamMan. This is the hardware generated NMI interrupt that is used by the system to perform realtime activitys such as loop managmenet and MIDI clock. In normal operation, the JamMan's host processor (Z80) gets an NMI interrupt about twice a millisecond (512us).
If the test fails, the letter "E" is displayed on the JamMan.