Table 3—Six monitor commands are available. The half-duplex communications are handled on a single pin. Note 
that the monitor will echo each input byte received.					
													
Command Op-byte Operand Return Action
READ $4A ADRSH:ADRSL Contents of specified address Retrieve value located at 16-bit address
WRITE $49 ADRSH:ADRSL:DATA None Put value into 16-bit address location
IREAD $1A None

Contents of next two addresses

(auto incrementing)

Retrieve the next two values located at the last 16-bit address + 1 and address + 2
IWRITE $19 Data None Put value into the last 16-bit address + 1
READSP $0C None SP + 1 as 2 bytes SPH:SPL This allows you to locate the stack. You can alter the PC loaded on the stack at SP+5:SP+6.
RUN $28 None PULH and RTI Unload the stack and execute at PC