IP2022 User’s Manual—Instruction Set Architecture www.ubicom.com 163 IWRITE Write External/Program RAM Operation: (ADDRX || ADDRH || ADDRL) = DATAH || DATAL Bits affected: None Opcode: 0000 0000 0001 1000 Description: This instruction transfers data from data memory
to  external  RAM  or  program  RAM.  The  24-bit
ADDRX/ADDRH/ADDRL   register   specifies   the
address of a 16-bit word which is loaded into the
contents  of  the  DATAH/DATAL  register.  If  the
address is not in external RAM or program RAM,
no   operation   is   performed.   The   instruction   is
blocking (i.e. no other instructions may execute
until it completes) when it is used to write program
RAM.  The instruction is non-blocking when it is
used to write external RAM. Cycles: 4 (blocking)/1 (non-blocking)