Differences

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--- system_routines:math [2016/06/02 10:04]
ex_writer [SETW]
+++ system_routines:math [2016/06/14 10:41]
ex_writer [DADD]
@@ Line 7: / Line 7: @@
 Undocumented routines are marked with an asterisk (*)
+<WRAP todo>Need documentation for most math routines</WRAP>
 ^ Name ^ Description ^
-| [[#bcdadd|BCDADD]]* | BCD add |
+| [[#BCDADD]]* | BCD add |
-| [[#bcdchs|BCDCHS]]* | BCD change sign |
+| [[#BCDCHS]]* | BCD change sign |
 | [[#bcddiv|BCDDIV]]* | BCD divide |
 | [[#bcdmul|BCDMUL]]* | BCD multiply |
@@ Line 35: / Line 37: @@
 | Calling Sequence: | <code z80>SYSTEM    BCDADD</code> or <code z80>SYSSUK    BCDADD
-DW       ()
+DW       (arg 1)
-DW       ()
+DB       (size/2 + 1)
-DB       ()</code>|
+DW       (arg 2)</code>|
 | Arguments: | B = SIZE/2 + 1\\ DE = Argument 1\\ HL = Argument 2 |
 | Output: | DE = Answer |
@@ Line 45: / Line 47: @@
 BCD CHANGE SIGN
+| Calling Sequence: | <code z80>SYSTEM    BCDCHS</code> or <code z80>SYSSUK    BCDCHS
+DB       ()
+DW       ()</code>|
+| Arguments: | B =\\ HL = |
+| Output: |  |
+| Notes: | None |
+| Description: |  |
 ==== BCDDIV ====
 BCD DIVISION
+| Calling Sequence: | <code z80>SYSTEM    BCDDIV</code> or <code z80>SYSSUK    BCDDIV
+DW       (arg 1)
+DB       ()
+DW       (arg 2)</code>|
+| Arguments: | B = \\ DE = \\ HL = Argument 2 |
+| Output: | ??? |
+| Notes: | None |
+| Description: |  |
 ==== BCDMUL ====
 BCD MULTIPLY
+| Calling Sequence: | <code z80>SYSTEM    BCDMUL</code> or <code z80>SYSSUK    BCDMUL
+DW       (arg 1)
+DB       ()
+DW       (arg 2)</code>|
+| Arguments: | B =\\ DE =\\ HL = |
+| Output: | DE = Answer |
+| Notes: | None |
+| Description: |  |
 ==== BCDNEG ====
 BCD NEGATE TO DECIMAL
+| Calling Sequence: | <code z80>SYSTEM    BCDNEG</code> or <code z80>SYSSUK    BCDNEG
+DW       ()
+DB       ()</code>|
+| Arguments: | B =\\ DE = |
+| Output: | ??? |
+| Notes: | None |
+| Description: |  |
 ==== BCDSUB ====
 BCD SUBTRACTION
+| Calling Sequence: | <code z80>SYSTEM    BCDSUB</code> or <code z80>SYSSUK    BCDSUB
+DW       (arg 1)
+DB       ()
+DW       (arg 2)</code>|
+| Arguments: | B =\\ DE =\\ HL = |
+| Output: | DE = Answer |
+| Notes: | None |
+| Description: |  |
 ==== DABS ====
 DECIMAL ABSOLUTE VALUE
+| Calling Sequence: | <code z80>SYSTEM    DABS</code> or <code z80>SYSSUK    DABS
+DW       ()
+DB       ()</code>|
+| Arguments: | B =\\ DE = |
+| Output: |  |
+| Notes: | None |
+| Description: |  |
 ==== DADD ====
 DECIMAL ADDITION
+| Calling Sequence: | <code z80>SYSTEM    DADD</code> or <code z80>SYSSUK    DADD
+DW       (arg 1)
+DB       ()
+DW       (arg 2)</code>|
+| Arguments: | B = \\ DE = \\ HL = |
+| Output: | ??? |
+| Notes: | None |
+| Description: |  |
 ==== DSMG ====
@@ Line 74: / Line 136: @@
 | Arguments: | A = Displacement (0–255)\\ HL = Base address of table |
 | Output: | A = Entry looked up\\ HL = Address of entry looked up |
-| Notes: | None |
 | Description: | INDEXB returns the byte at address (Base address) + (Displacement) |
-| Restrictions: | None |
 ==== INDEXN ====
@@ Line 88: / Line 148: @@
 | Notes: | Indexing illustration below |
 | Description: | INDEXN looks up a specified nibble in a linear list. |
-| Restrictions: | None |
 {{:indexn.png}}
@@ Line 112: / Line 171: @@
 DW       (source)</code>|
 | Arguments: | DE = Destination address\\ HL = Source address\\ BC = Number of bytes to transfer |
-| Notes: | None |
 | Description: | MOVE uses LDIR to copy bytes from source to destination. |
-| Restrictions: | None |
 ==== NEGT ====
 DECIMAL NEGATE
+| Calling Sequence: | <code z80>SYSTEM    NEGT</code> or <code z80>SYSSUK    NEGT
+DB       (B)
+DW       (HL)</code>|
+| Arguments: | B =\\ HL = |
+| Output: | ??? |
+| Notes: | None |
+| Description: |  |
 ==== RANGED ====
@@ Line 127: / Line 192: @@
 | Arguments: | A = Range |
 | Output: | A = Random Number (0 to Range - 1) |
-| Notes: | If N is a power of 2, it is considerably faster to use N=0, which causes an 8-bit value to be returned without ranging. Use an AND instruction to range it yourself.\\ \\ RANGED uses a polynomial shift register RANSHT in [[system rom#system ram memory cells|system RAM]]. RANGED is called in [[human interface#getnum|GETNUM]] while waiting for game selection/parameter entry. Thus each execution of a program will receive different random numbers. For 'predictable' random numbers, alter RANSHT yourself after parameter acceptance. |
+| Notes: | If N is a power of 2, it is considerably faster to use N=0, which causes an 8-bit value to be returned without ranging. Use an AND instruction to range it yourself.\\ \\ RANGED uses a polynomial shift register RANSHT in [[software:system rom#system ram memory cells|system RAM]]. RANGED is called in [[human interface#getnum|GETNUM]] while waiting for game selection/parameter entry. Thus each execution of a program will receive different random numbers. For "predictable" random numbers, alter RANSHT yourself after parameter acceptance. |
 | Description: | Returns a ranged random number. |
-| Restrictions: | None |
 ==== SETB ====
@@ Line 156: / Line 220: @@
 | Calling Sequence: | <code z80>SYSTEM    ????</code>|
 | Arguments: |  |
-| Notes: | Currently undocumented |
+| Notes: |  |
 | Description: | Shift up digit in A |
-| Restrictions: | None |
 ==== STOREN ====
@@ Line 166: / Line 229: @@
 DW       (base address)</code>|
 | Arguments: | C = Nibble displacement (not loaded)\\ HL = Base address\\ A = Nibble value to store (not loaded) |
-| Notes: | None |
+| Description: | STOREN is the inverse of [[#INDEXN]] but functions identically. |
-| Description: | STOREN is the inverse of [[math routines#indexn|INDEXN]] but functions identically. |
-| Restrictions: | None |