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Elite on the BBC Micro and NES

Workspaces: ZP

[6502 Second Processor version, I/O processor]

Name: ZP [Show more] Type: Workspace Address: &0080 to &0089 Category: Workspaces Summary: Important variables used by the I/O processor
Context: See this workspace in context in the source code Variations: See code variations for this workspace in the different versions References: No direct references to this workspace in this source file
ORG &0080 .ZP SKIP 0 \ The start of the zero page workspace .P SKIP 1 \ Temporary storage, used in a number of places \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADD \ * DIALS (Part 2 of 4) \ * DIALS (Part 3 of 4) \ * DVID4 \ * HANGER \ * LOIN (Part 1 of 7) \ * LOIN (Part 2 of 7) \ * LOIN (Part 5 of 7) \ * LOIN (Part 6 of 7) \ * LOIN (Part 7 of 7) \ * PIXEL \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.Q SKIP 1 \ Temporary storage, used in a number of places \ \ [Show more]
\ \ This variable is used by the following: \ \ * DIALS (Part 3 of 4) \ * DIL2 \ * DILX \ * DVID4 \ * HANGER \ * HLOIN \ * HLOIN2 \ * LOIN (Part 1 of 7) \ * LOIN (Part 2 of 7) \ * LOIN (Part 3 of 7) \ * LOIN (Part 4 of 7) \ * LOIN (Part 5 of 7) \ * PIXEL \ * SC48 \ * TT26 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.R SKIP 1 \ Temporary storage, used in a number of places \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADD \ * DIALS (Part 2 of 4) \ * DILX \ * HANGER \ * HLOIN \ * LOIN (Part 2 of 7) \ * LOIN (Part 3 of 7) \ * LOIN (Part 4 of 7) \ * LOIN (Part 5 of 7) \ * LOIN (Part 6 of 7) \ * LOIN (Part 7 of 7) \ * TT26 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.S SKIP 1 \ Temporary storage, used in a number of places \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADD \ * DIALS (Part 2 of 4) \ * HANGER \ * HLOIN \ * LOIN (Part 1 of 7) \ * LOIN (Part 3 of 7) \ * LOIN (Part 4 of 7) \ * LOIN (Part 6 of 7) \ * LOIN (Part 7 of 7) \ * PIXEL \ * TT26 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.T SKIP 1 \ Temporary storage, used in a number of places \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADD \ * HANGER \ * HLOIN \ * MSBAR \ * TT26 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.SWAP SKIP 1 \ Temporary storage, used to store a flag that records \ whether or not we had to swap a line's start and end \ coordinates around when clipping the line in routine \ LL145 (the flag is used in places like BLINE to swap \ them back) \ \ [Show more]
\ \ This variable is used by the following: \ \ * LOIN (Part 1 of 7) \ * LOIN (Part 2 of 7) \ * LOIN (Part 3 of 7) \ * LOIN (Part 4 of 7) \ * LOIN (Part 5 of 7) \ * LOIN (Part 6 of 7) \ * LOIN (Part 7 of 7) \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.T1 SKIP 1 \ Temporary storage, used in a number of places \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADD \ * ADDBYT \ * DIALS (Part 1 of 4) \ * DIALS (Part 3 of 4) \ * DIALS (Part 4 of 4) \ * DILX \ * PIXEL \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.COL SKIP 1 \ Temporary storage, used to store colour information \ when drawing pixels in the dashboard \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADDBYT \ * CPIX2 \ * DILX \ * DOCOL \ * DOT \ * HLOIN2 \ * LOIN (Part 3 of 7) \ * LOIN (Part 4 of 7) \ * LOIN (Part 6 of 7) \ * LOIN (Part 7 of 7) \ * SC48 \ * STARTUP \ * TT26 \ * TTX66 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.OSSC SKIP 2 \ When the parasite sends an OSWORD command to the I/O \ processor (i.e. an OSWORD with A = 240 to 255), then \ the relevant handler routine in the I/O processor is \ called with OSSC(1 0) pointing to the OSWORD parameter \ block (i.e. OSSC(1 0) = (Y X) from the original call \ in the I/O processor) \ \ [Show more]
\ \ This variable is used by the following: \ \ * DODKS4 \ * DOT \ * HANGER \ * HLOIN \ * KEYBOARD \ * MSBAR \ * NWOSWD \ * PIXEL \ * SC48 \ * SOMEPROT \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
ORG &0090 .XX15 SKIP 0 \ Temporary storage, typically used for storing screen \ coordinates in line-drawing routines \ \ There are six bytes of storage, from XX15 TO XX15+5. \ The first four bytes have the following aliases: \ \ X1 = XX15 \ Y1 = XX15+1 \ X2 = XX15+2 \ Y2 = XX15+3 \ \ These are typically used for describing lines in terms \ of screen coordinates, i.e. (X1, Y1) to (X2, Y2) \ \ The last two bytes of XX15 do not have aliases \ \ [Show more]
\ \ This variable is used by the following: \ \ * DIALS (Part 3 of 4) \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.X1 SKIP 1 \ Temporary storage, typically used for x-coordinates in \ line-drawing routines \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADDBYT \ * CPIX2 \ * DOT \ * HLOIN \ * HLOIN2 \ * LOIN (Part 1 of 7) \ * LOIN (Part 2 of 7) \ * LOIN (Part 5 of 7) \ * SC48 \ * TTX66 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.Y1 SKIP 1 \ Temporary storage, typically used for y-coordinates in \ line-drawing routines \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADDBYT \ * CPIX2 \ * CPIX4 \ * DOT \ * HLOIN \ * LOIN (Part 1 of 7) \ * LOIN (Part 2 of 7) \ * LOIN (Part 5 of 7) \ * SC48 \ * TTX66 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.X2 SKIP 1 \ Temporary storage, typically used for x-coordinates in \ line-drawing routines \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADDBYT \ * HLOIN \ * LOIN (Part 1 of 7) \ * LOIN (Part 2 of 7) \ * LOIN (Part 5 of 7) \ * TTX66 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.Y2 SKIP 1 \ Temporary storage, typically used for y-coordinates in \ line-drawing routines \ \ [Show more]
\ \ This variable is used by the following: \ \ * ADDBYT \ * HLOIN \ * HLOIN2 \ * LOIN (Part 1 of 7) \ * LOIN (Part 2 of 7) \ * LOIN (Part 5 of 7) \ * TTX66 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
SKIP 2 \ The last 2 bytes of the XX15 block .SC SKIP 1 \ Screen address (low byte) \ \ Elite draws on-screen by poking bytes directly into \ screen memory, and SC(1 0) is typically set to the \ address of the character block containing the pixel \ we want to draw \ \ [Show more]
\ \ This variable is used by the following: \ \ * CLYNS \ * CPIX2 \ * DIALS (Part 1 of 4) \ * DIALS (Part 4 of 4) \ * DIL2 \ * DILX \ * DOBULB \ * ECBLB \ * HAL3 \ * HANGER \ * HAS2 \ * HAS3 \ * HLOIN \ * LOIN (Part 2 of 7) \ * LOIN (Part 3 of 7) \ * LOIN (Part 4 of 7) \ * LOIN (Part 5 of 7) \ * LOIN (Part 6 of 7) \ * LOIN (Part 7 of 7) \ * MSBAR \ * PIXEL \ * SC48 \ * TT26 \ * USOSWRCH \ * ZES1 \ * ZES2 \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above
.SCH SKIP 1 \ Screen address (high byte) \ \ [Show more]
\ \ This variable is used by the following: \ \ * MSBAR \ \ This list only includes code that refers to the \ variable by name; there may be other references to \ this memory location that don't use this label, and \ these will not be mentioned above