OVEREXTENDED MNEMONICS ARRN Add and reset to random number BB Branch on bug BBI Branch on burned-out indicator BBO Branch on bathtub overflow BCF Branch on chip box full BCH Branch on carry flag at half mast BD Backspace disk BPO Branch on power off BS Branch sometimes BSC Burst selector channel BSO Branch on sleepy operator BTI Blow trumpet immediately CCS Chinese character set CRN Convert to Roman Numerals DAC Divide and conquer DAD Disable address and data lines DD Destroy disk DO Divide and overflow DPK Destroy storage protect key DZSR Divide by zero and store remainder ECP Erase card punch ED Eject disk EIO Execute invalid op-code EN Emulate Nintendo EROS Erase read-only storage FSG Fill screen with garbage FSR Forms skip and run away HCF Halt and catch fire IA Illogical and II Interrupt and ignore IL Infinite loop IOR Illogical or IRB Invert record and branch IRT Ignore write-protect tab LCC Load and clear core LIA Load ineffective address LMB Lose message and branch LRB Lose register byte MLR Move and lose record MTI Make tape invalid MWC Move and warp core NPN No program necessary OCS Overwrite code segment OOS Override operating system PBC Print and break chain PI Punch invalid PO Punch operator PPSW Pack program status word PS Print and smear RBT Read blank tape RCR Rewind card reader RCS Read card and scramble data RDI Reverse drum immediately RID Read invalid data RIG Read inter-record gap RBT Rewind and break tape RIM Read instruction manual RM Refresh memory RNR Read noise record ROM Read operator's mind RPM Read programmer's mind RPB Read, print and blush RRCR Rotate right cash register RRR Read record and run away RSC Rewind system clock RSO Resume on stack overflow RT Reduce throughput SC Scramble channels SD Slip disk SDRB Search and destroy register byte SLC Shift left continuous SLP Sharpen light pencil SPSW Scramble program status word SRCC Select reader and chew cards SRSD Seek record and scar disk SSJ Select stacker and jam TAB Throw away byte TAM Transfer accumulator to Minneapolis TPO Turn power off TVT Test vacuum tubes UCB Uncouple CPU and branch UER Update and erase record UPC Uncouple program counter WB Wait for bus WG Wait for Godot WBT Write blank tape WI Wetware interrupt WNR Write noise record WRS Write to ROM storage WWLW Write wrong length word XNH Execute no-op and hang XUI Execute undefined instruction