Introduction
Arithmetic Operations -- Add, Subtract, Multiply, Divide
Complement Operations -- Negate (2's Comp) and Complement (1's)
Rotate and Shift Operations -- Left and Right
Logical Operations -- And, Or, Xor
:Introduction

     Thió  modulå  containó á seô oæ 16-biô  unsigneä  arithmetiã �
routines®   Alì routineó uså HÌ aó thå accumulatoò oò thå result¬ �
anä  HÌ anä DÅ contaiî thå operandó requireä (iæ onlù onå operanä �
is needed, HL contains it).

     The available routines are:

          ADDHD -- HL = HL + DE    SUBHD -- HL = HL - DE
          MULHD -- HL = HL * DE    DIVHD -- HL = HL / DE
          NEGH  -- HL = 2's Complement of HL
          CMPH  -- HL = 1's Complement of HL
          ROTLH -- HL is rotated left one bit position
          ROTRH -- HL is rotated right one bit position
          SHFTLH -- HL is shifted left one bit position
          SHFTRH -- HL is shifted right one bit position
          ANDHD  -- HL = HL AND DE
          ORHD   -- HL = HL OR DE
          XORHD  -- HL = HL XOR DE

:Arithmetic Operations -- ADDHD, SUBHD, MULHD, DIVHD

     Alì  oæ  theså routineó operatå oî HÌ anä  DE¬  placinç  thå �
resulô  iî HL®   Thå Carrù Flaç ió affected¬  frequentlù useä  tï �
indicate overflow.


     Routine Name:  ADDHD
     Functionº
          HL = HL + DE
     Inputs:  HL, DE are operands
     Outputs:  HL is result, Carry Flag Set (C) means overflow
     Registers Affected:  HL, PSW
     SYSLIB Routines Called:  None
     Speciaì  Erroò Conditionsº  None


     Routine Name:  SUBHD
     Functionº
          HL = HL - DE
     Inputs:  HL, DE are operands
     Outputs:  HL is result, Carry Flag Set (C) if HL<DE
     Registers Affected:  HL, PSW
     SYSLIB Routines Called:  None
     Speciaì  Erroò Conditionsº  None


     Routine Name:  MULHD
     Functionº
          HL = HL * DE
     Inputs:  HL, DE are operands
     Outputs:  HL is result, Carry Set means Overflow
     Registers Affected:  HL, PSW
     SYSLIB Routines Called:  SHFTRH, SHFTLH
     Speciaì  Erroò Conditionsº  None
     Noteº   Thió  routinå ió optimizeä foò speed¬  witè á  minoò �
sacrificå  oî size¬  anä iô alwayó takeó 1¶ loopó tï perforí  anù �
multiplication.


     Routine Name:  DIVHD
     Functionº
          HL = HL / DE
     Inputs:  HL, DE are operands
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  SHFTLH
     Speciaì  Erroò Conditionsº  None
     Noteº   Thió  routinå ió optimizeä foò speed¬  witè á  minoò �
sacrificå  oî size¬  anä iô alwayó takeó 1¶ loopó tï perforí  anù �
division.

:Complement Operations -- NEGH and CMPH

     These routines operate on HL, placing the result into HL.


     Routine Name:  NEGH
     Functionº
          HL = 2's Complement of HL
     Inputs:  HL is operand
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  CMPH
     Speciaì  Erroò Conditionsº  None


     Routine Name:  CMPH
     Functionº
          HL = 1's Complement of HL
     Inputs:  HL is operand
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None
     Speciaì  Erroò Conditionsº  None

:Rotate and Shift Operations -- ROTLH, ROTRH, SHFTLH, SHFTRH


     These operations operate on HL, placing the result into HL.


     Routine Name:  ROTLH
     Functionº
          HÌ  ió  rotateä  lefô onå  biô  position®   Thió  ió  á �
circulaò  rotate¬  anä  thå mosô significanô biô oæ È ió  rotateä �
into the least significant bit position of L.
     Inputs:  HL is operand
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None
     Speciaì  Erroò Conditionsº  None


     Routine Name:  ROTRH
     Functionº
          HÌ  ió  rotateä  righô onå biô  position®   Thió  ió  á �
circulaò  rotate¬  anä thå leasô significanô biô oæ Ì ió  rotateä �
into the most significant bit position of H.
     Inputs:  HL is operand
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None
     Speciaì  Erroò Conditionsº  None


     Routine Name:  SHFTLH
     Functionº
          HÌ  ió  shifteä  lefô  onå  biô  position®   Thå  leasô �
significant bit of L is filled with a Zero.
     Inputs:  HL is operand
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None  
     Speciaì  Erroò Conditionsº  None


     Routine Name:  SHFTRH
     Functionº
          HÌ  ió  shifteä  righô  onå  biô  position®   Thå  mosô �
significant bit of H is filled with a Zero.
     Inputs:  HL is operand
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None  
     Speciaì  Erroò Conditionsº  None

:Logical Operations -- ANDHD, ORHD, XORHD

     These operate on HL and DE, placing the result into HL.


     Routine Name:  ANDHD
     Functionº
          HL = HL AND DE
     Inputs:  HL and DE are operands
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None  
     Speciaì  Erroò Conditionsº  None


     Routine Name:  ORHD
     Functionº
          HL = HL OR DE
     Inputs:  HL and DE are operands
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None  
     Speciaì  Erroò Conditionsº  None


     Routine Name:  XORHD
     Functionº
          HL = HL XOR DE
     Inputs:  HL and DE are operands
     Outputs:  HL is result
     Registers Affected:  HL
     SYSLIB Routines Called:  None
     Speciaì  Erroò Conditionsº  None