ND-1xx Instructions

See also: ND-1xx Instructions Sorted Numerically

Instruction Set
NORD-10/ND-100/ND-120 instructions are all exactly 16 bits (1 word) long. Addressing mode, displacement, source register, destination register are, when applicable, encoded inside the 16-bit instruction word itself.

Store Instructions

 * STZ – Store zero
 * STA – Store A
 * STT – Store T
 * STX – Store X
 * MIN – Memory increase, skip if zero

Load Instructions

 * LDA – Load A
 * LDT – Load T
 * LDX – Load X

Arithmetic and Logical Instructions

 * ADD – Add to A (C, O and Q may also be affected)
 * SUB – Subtract from A (C, O and Q may also be affected)
 * AND – Logical AND to A
 * ORA – Logical inclusive OR to A
 * MPY – Multiply integer (O and Q may also be affected)

Double Word Instructions

 * LDD – Load double word
 * STD – Store double word

Floating Instructions

 * LDF – Load floating accumulator
 * STF – Store floating accumulator
 * FAD – Add to floating accumulator (TG may also be affected)
 * FSB – Subtract from floating accumulator (TG may also be affected)
 * FMU – Multiply floating accumulator (TG may also be affected)
 * FDV – Divide floating accumulator (Z and TG may also be affected)

Byte Instructions

 * BFILL – Byte fill
 * MOVB – Move bytes
 * MOVBF – Move bytes forward
 * SBYT – Store byte
 * LBYT – Load byte

Execute Instruction

 * EXR – Execute instruction found in specified register

Argument Instructions

 * AAA – Add argument to A
 * AAB – Add argument to B
 * AAT – Add argument to T
 * AAX – Add argument to X
 * SAA – Set argument to A
 * SAB – Set argument to B
 * SAT – Set argument to T
 * SAX – Set argument to X

Bit Instructions

 * BSKP – Skip next location if specified condition is true
 * BSET – Set specified bit equal to specified condition
 * BSTA – Store and clear K
 * BSTC – Store complement and set K
 * BLDA – load K
 * BLDC – Load bit complement to K
 * BANC – Logical AND with bit complement
 * BORC – Logical OR with bit complement
 * BAND – Logical AND to K
 * BORA – Logical OR to K

Shift Instructions

 * SHT – Shift T register
 * SHD – Shift D register
 * SHA – Shift A register
 * SAD – Shift A and D registers connected

Subinstructions (Types)
For each shift instruction, one of the following types can be specified
 * nil (default) Arithmetic shift
 * ROT – Rotational shift
 * ZIN – Zero end input
 * LIN – Link end input

Subinstructions (Direction)

 * nil (default) Left shift
 * SHR – Right shift

System Control Instructions

 * IOF – Interrupt system off
 * ION – Interrupt system on
 * LWCS – Load Writeable Control Store
 * MON – Monitor Call
 * PIOF – Memory management and interrupt system off
 * PION – Memory management and interrupt system on
 * POF – Memory management off
 * PON – Memory management on
 * REX – Reset extended address mode
 * SEX – Set extended address mode
 * WAIT – Wait (give up priority)
 * OPCOM – Operator's Communication Code

Load Independent Instructions

 * TRA – Transfer to A register
 * TRR – Transfer to register

Inter-level Instructions

 * IRR – Inter Register Read
 * IRW – Inter Register Write

Index register operation

 * MIX3 – Multiply index by 3

Arithmetic Operations, RAD=1:

 * RADD – Register addition
 * RSUB – Register subtraction
 * COPY – Register transfer

Subinstructions

 * AD1 – Also add 1 to destination
 * ADC – Also add old carry to destination

Logical Operations, RAD=0:

 * SWAP – Register exchange
 * RAND – Register logical AND
 * REXO – Register logical exclusive OR
 * RORA – Register logical OR

Subinstructions

 * CLD – Clear destination register before operation
 * CM1 – Use complement (ones' complement) of source register as operand.

Combined Instructions:

 * EXIT – Return from subroutine
 * RCLR – Register clear
 * RINC – Register increment
 * RDCR – Register decrement

Extended Arithmetic Operations:

 * RMPY – Integer inter-register multiply
 * RDIV – Integer inter-register divide

Floating Conversion

 * NLZ – Normalize (integer to floating)
 * DNZ – Denormalize (floating to integer)

Memory Examine/Deposit Instructions

 * EXAM – Memory examine
 * DEPO – Memory deposit

Unconditional Jump

 * JMP – Jump
 * JPL – Jump to subroutine

Conditional Jump

 * JAP – Jump if A register is positive or zero
 * JAN – Jump if A register is negative
 * JAZ – Jump if A register is zero
 * JAF – Jump if A register is filled (not zero)
 * JXN – Jump lf X register is negative
 * JXZ – Jump if X register is zero.
 * JPC – Count and jump if X register is positive or zero.
 * JNC – Count and jump if X register is negative.

Skip Instructions

 * SKP – Skip next instruction if specified condition is true

Subinstructions (Specified condition)

 * EQL – Equal
 * GEQ – Signed greater or equal to (owerflow not OK)
 * GRE – Signed greater or equal to (owerflow OK)
 * MGRE – Magnitude greater or equal to
 * UEQ – Unequal to
 * LSS – Signed less than (owerflow not OK)
 * LST – Signed less than (owerflow OK)
 * MLST – Magnitude less than

Dummys (may be used to obtain easy readability)

 * IF
 * 0

Decimal Instructions

 * ADDD – Add decimal
 * SUBD – Subtract decimal
 * COMD – Compare decimal
 * SHDE – Decimal shift
 * PACK – Convert to packed decimal
 * UNPACK – Convert to unpacked decimal

Stack Handling Instructions

 * INIT – Initialize stack
 * ENTR – Enter stack
 * LEAVE – Leave stack
 * ELEAV – Error leave stack

Additional instructions in the CX option
The CX instructions include the CE instructions in improved versions, plus the following CX-only instructions:
 * MOVEW – Move block of words
 * TSET – Test and set
 * RDUS – Read don't use cache

SINTRAN-III Segment Change Instructions

 * SETPT – Set page tables
 * CLEPT – Clear page tables
 * CLNREENT – Clear non reentrant
 * CHREENTPAGES – Change not reentrant pages
 * CLEPU – Clear page tables, collect PGU information

New SINTRAN instructions in ND-110

 * CLPT Clear segment from page tables
 * CNREK Clear non re-entrant pages
 * ENPT Enter segment in page tables
 * INSPL Insert page in page list
 * REMPL Remove page from page list
 * REPT Enter re-entrant segment in page tables

Undocumented instructions

 * GECO
 * IOT