kernal-memory.inc.html; generated on Fri Sep 18 21:44:55 2015 by ca65html
uz@cc65.org
1: .segment "MEM_KERNAL_ZP": zeropage
2:
3: zSTATUS: .res 1 ; $0090 ; status of TAPE/IEC routines
4:
5: zSTKEY: .res 1 ; $0091
6: zSVXT: .res 1 ; $0092
7: zVERCKK: .res 1 ; $0093 ; verify flag: Remember in KLOAD if LOAD (=0) or VERIFY (=1) is requested.
8: zC3PO: .res 1 ; $0094 ; delayed byte for IEC output
9: ; As an EOI must be signaled BEFORE the last byte is transferred,
10: ; the KERNAL routines use a delayed write approach:
11: ;
12: ; It starts with zC3PO = 0.
13: ; When the first byte to be output is given to the IEC routines,
14: ; it is written to zBSOUR, and zC3PO.7 is set.
15: ; When the next byte is written, zC3PO is tested. As it is negative,
16: ; the byte in zBSOUR is being output to the IEC bus. Afterwards,
17: ; the new byte is written into zBSOUR.
18: ; When the last byte is transferred, the next command transmitted
19: ; (i.e. LISTEN, TALK, UNLISTEN, UNTALK) tests for zC3PO. As it is
20: ; negative, the last byte (in zBSOUR) is output to the IEC bus, and
21: ; an EOI is signalled.
22: ;
23: zBSOUR: .res 1 ; $0095 ; The byte to write on the IEC bus. (see also zC3PO)
24: zSYNO: .res 1 ; $0096
25: zTEMPX: .res 1 ; $0097
26: zLDTND: .res 1 ; $0098 ; number of active entries in the lLAT, lFAT and lSAT table
27: zDFLTN: .res 1 ; $0099
28: zDFLTO: .res 1 ; $009A
29: zPRTY: .res 1 ; $009B
30: zDPSW: .res 1 ; $009C
31: zNSGFLG: .res 1 ; $009D ; message output policy:
32: ; bit 7: Output "Loading", "Saving", "Verifying", "Found", ... messages
33: ; bit 6: Output "I/O ERROR #n" if KERNAL routines encounter an error
34: ; This value is only set by kSETMSG.
35:
36: zPTR1: .res 1 ; $009E
37: zPTR2: .res 1 ; $009F
38: zTIME: .res 3 ; $00A0
39: zTSFCNT: .res 1 ; $00A3 ; mark: signal EOI (== $80) or not (== $00) on IEC bus.
40: zTBTCNT: .res 1 ; $00A4
41: zCNTDN: .res 1 ; $00A5
42: zBUFPNT: .res 1 ; $00A6 ; pointer into tape buffer (lTBUFFR), stored as an index 0..(TBUFFR_SIZE - 1): Contains the last value that was written or read.
43: zINBIT: .res 1 ; $00A7
44: zBITC1: .res 1 ; $00A8
45: zRINONE: .res 1 ; $00A9
46: zRIDATA: .res 1 ; $00AA
47: zRIPRTY: .res 1 ; $00AB
48: zSAL: .res 2 ; $00AC
49: zEAL: .res 2 ; $00AE
50: zCMPO: .res 2 ; $00B0
51: zTAPE1: .res 2 ; $00B2
52: zBITTS: .res 1 ; $00B4
53: zNXTBIT: .res 1 ; $00B5
54: zRODATA: .res 1 ; $00B6
55: zFNLEN: .res 1 ; $00B7 ; length of the name of the file to be opened. Address at zFNADR. Only used on OPEN and LOAD.
56: zLA: .res 1 ; $00B8 ; logical device number of current open file (or in preparation to a call to OPEN)
57: zSA: .res 1 ; $00B9 ; device (primary) address of current open file (or in preparation to a call to OPEN)
58: zFA: .res 1 ; $00BA ; secondary address of current open file (or in preparation to a call to OPEN)
59: zFNADR: .res 2 ; $00BB ; address of the name of the file to be opened. Length at zFNLEN. Only used on OPEN and LOAD.
60: zROPRTY: .res 1 ; $00BD
61: zFSBLK: .res 1 ; $00BE
62: zMYCH: .res 1 ; $00BF
63: zCAS1: .res 1 ; $00C0 ; 0 if no tape operation in progress, != 0 otherwise. Use in the IRQ routine to switch off tape motor, if needed.
64: zSTAL: .res 2 ; $00C1
65: zMEMUSS: .res 2 ; $00C3
66: zLSTX: .res 1 ; $00C5 ; last pressed key. That is, after keyboard scanning completes, this becomes a copy of zSFDX. This is used for determining if key repetition is to be performed.
67: zNDX: .res 1 ; $00C6 ; current numbers of characters in the keyboard buffer (lKEYD). The maximum is stored in lXMAX.
68: zRVS: .res 1 ; $00C7
69: zINDX: .res 1 ; $00C8
70: zLXSP: .res 1 ; $00C9
71: zTEMP_zPNTR: .res 1 ; $00CA ; temporary buffer for cursorpos (zPNTR) inside of BASIN
72: zSFDX: .res 1 ; $00CB ; key code if the code that is currently found pressed
73: zBLNSW: .res 1 ; $00CC ; blink switch: <> 0 -> disable cursor, == 0 -> enable cursor
74: zBLNCT: .res 1 ; $00CD
75: zGDBLN: .res 1 ; $00CE
76: zBLNON: .res 1 ; $00CF ; current blink state: 0 = cursor currently invisible, 1 = cursor is just now visible on the screen
77: zCRSW: .res 1 ; $00D0 ; used in editor routines for sreen input: > 0 if CR has been pressed, 0 if there has not been any input yet (or no CR has been pressed yet)
78: zPNT: .res 2 ; $00D1 ; pointer to start of current cursor row in video RAM (cf. zUSER)
79: zPNTR: .res 1 ; $00D3 ; column of current cursor position (0 ... X-1)
80: zQTSW: .res 1 ; $00D4 ; quotation mark switch: 1 = we are in quotation mode, 0 = we are not.
81: zLNMX: .res 1 ; $00D5 ; maximum column number in the current (logical) line
82: zTBLX: .res 1 ; $00D6 ; row of current cursor positon (0 ... Y-1)
83: zSCHAR: .res 1 ; $00D7 ; temporary storage for a character in editor routines for input and output, and temporary storage in tape routines
84: zINSRT: .res 1 ; $00D8 ; number of characters to output in INSERT mode. 0 = we are not in insert mode
85: zLDTB1: .res 26 ; $00D9 ; high byte of start address of (logical) screen rows
86: ; Bit 7 ($80) is 1 if this line is "stand-alone";
87: ; it is 0 if this line is combined with the previous one
88: ; the lower bits (and #>lVIDEORAM_SIZE) define the high byte bits of the start address of this row.
89: ;
90: ; For the last row, this table entry contains $FF as an end marker.
91:
92: zUSER: .res 2 ; $00F3 ; pointer to start of current cursor row in color RAM (cf. zPNT)
93: zKEYTAB: .res 2 ; $00F5
94: zRIBUF: .res 2 ; $00F7 ; pointer to the RS232 input buffer (ring buffer) (see also lRIDBE, lRIDBS)
95: zROBUF: .res 2 ; $00F9 ; pointer to the RS232 output buffer (ring buffer) (see also lRODBE, lRODBS)
96: zFREKXP: .res 4 ; $00FB
97:
98: .segment "MEM_KERNAL_DATA_0200"
99:
100: ; the following table contains the data (logical file number, primary address, secondary address) for open files.
101: ; The entries correspond to each other: That is, lLAT + x, lFAT + x and lSAT + x contain the data for the file
102: ; with the index (*not* logical file number!) x.
103:
104: lLAT_Size := 10
105: lLAT: .res lLAT_Size ; $0259 ; table of logical file numbers for open files. Number of active entries in zLDTND. Cannot be 0 for active files.
106: lFAT: .res lLAT_Size ; $0263 ; table of device (primary) addresses for open files. Number of active entries in zLDTND.
107: lSAT: .res lLAT_Size ; $026D ; table of secondary addresses for open files. Number of active entries in zLDTND.
108:
109: lKEYD: .res 10 ; $0277
110: lMEMSTR: .res 2 ; $0281
111: lMEMSIZ: .res 2 ; $0283
112: lTIMOUT: .res 1 ; $0285
113: lCOLOR: .res 1 ; $0286 ; default color (bit 7 must be 0, or CHROUT_SCREEN will behave erroneouskly!)
114: lGDCOL: .res 1 ; $0287
115: lHIBASE: .res 1 ; $0288 ; high byte of video RAM address
116: lXMAX: .res 1 ; $0289 ; maximum number of characters in the keyboard buffer (lKEYD). zNDX is checked against this value
117: lRPTFLG: .res 1 ; $028A ; repeat flag for keys
118: ; bit 7 ($80) == 1 -> repeat all keys
119: ; bit 6 ($40) == 1 -> do not repeat any key
120: ; else: Repeat special keys (space, CRSRS, INS/DEL), but not the others
121:
122: ; the test is done starting with bit 7, then bit 6.
123: ; thus, if both are set, all keys are repeated
124:
125: lKOUNT: .res 1 ; $028B ; delay counter for key repetitions. This is decremented on every IRQ, starting from 4.
126:
127: lDELAY: .res 1 ; $028C ; delay counter for key repetitions. It is used for the initial delay before the key repetition starts.
128:
129: lSHFLAG: .res 1 ; $028D ; contains the state of the shift keys while scanning the keyboard.
130: ; The state is an OR between the following values, if the correspondig key is pressed:
131: ; bit 0 ($01) = shift
132: ; bit 1 ($02) = C=
133: ; bit 2 ($04) = CTRL
134: lSHFLAG_SHIFT := $01
135: lSHFLAG_CBM := $02
136: lSHFLAG_CTRL := $04
137:
138: lLSTSHF: .res 1 ; $028E ; contains the *last* shift state. That is, after the keyboard is scanned, this becomes a copy of lSHFLAG. This way, the KERNAL prevents a repeated toggling when pressend SHIFT + C=
139: lKEYLOG: .res 2 ; $028F
140: lMODE: .res 1 ; $0291 ; determines editor mode.
141: ; bit 7 ($80) == 1 -> Switching between uppercase-mode and lowercase-mode via SHIFT + C= is not allowed
142: ; bit 4 ($10) == 1 -> TODO ??? (used in VIC20-02)
143: ; bit 3 ($08) == 1 -> we are in lowercase mode, == 0 -> we are in uppercase mode (only VIC20-02)
144: ; on VIC20-02, lMODE also contains the offset into the @KEYTABS_VEC table ($00-$16)
145:
146: ; on the VIC20-02, lMODE is used in CHROUT_SCREEN to determine if some chars are to
147: ; be translated (according to CHROUT_REPLACEMENT_TABLE). If lMODE is not 0, the
148: ; translation is done. If it is 0, the translation is skipped.
149:
150: lAUTODN: .res 1 ; $0292 ; TODO "Auto down" flag: (Flag: "combine line with next line, if needed")
151:
152: ; If the output is done because of some key press, lAUTODN is not 0. In this case,
153: ; when the output reaches the end of a row, this row is combined with the next
154: ; row. Furthermore, the screen contents below the current line are scrolled down.
155:
156: ; If the output is done without some key press, lAUTODN is 0. In this case,
157: ; when the output reaches the end of a row, this row is combined with the next
158: ; one, but the screen contents are NOT scrolled down.
159:
160: lM51CTR: .res 1 ; $0293
161: lM51CDR: .res 1 ; $0294
162: lM51AJB: .res 2 ; $0295
163: lRSSTAT: .res 1 ; $0297
164: lBITNUM: .res 1 ; $0298
165: lBAUDOF: .res 2 ; $0299
166: lRIDBE: .res 1 ; $029B ; RS232 input buffer at zRIBUF: read pointer
167: lRIDBS: .res 1 ; $029C ; RS232 input buffer at zRIBUF: write pointer
168: lRODBS: .res 1 ; $029D ; RS232 output buffer at zROBUF: read pointer
169: lRODBE: .res 1 ; $029E ; RS232 output buffer at zROBUF: write pointer
170: lIRQTMP: .res 2 ; $029F
171:
172: .if CompileComputer >= C64_GENERAL
173:
174: lENABL: .res 1 ; $02A1 ; CIA2 ICR temporary register
175: lTODSNS: .res 1 ; $02A2
176: lTRDTMP: .res 1 ; $02A3
177: lTD1IRQ: .res 1 ; $02A4
178: lTLNIDX: .res 1 ; $02A5
179: lTVSFLG: .res 1 ; $02A6
180:
181: .else
182:
183: lTLNIDX := $00F2
184:
185: .endif
186:
187: .segment "MEM_KERNAL_DATA_0300"
188:
189: lCINV: .res 2 ; $0314
190: lCNBINV: .res 2 ; $0316
191: lNMINV: .res 2 ; $0318
192: lIOPEN: .res 2 ; $031A
193: lICLOSE: .res 2 ; $031C
194: lICHKIN: .res 2 ; $031E
195: lICKOUT: .res 2 ; $0320
196: lICLRCH: .res 2 ; $0322
197: lIBASIN: .res 2 ; $0324
198: lIBSOUT: .res 2 ; $0326
199: lISTOP: .res 2 ; $0328
200: lIGETIN: .res 2 ; $032A
201: lICLALL: .res 2 ; $032C
202: lUSRCMD: .res 2 ; $032E
203: lILOAD: .res 2 ; $0330
204: lISAVE: .res 2 ; $0332
205:
206: .res 8 ; $0334 - $033B, unused
207:
208: lTBUFFR_SIZE := $00C0
209: lTBUFFR: .res lTBUFFR_SIZE ; $033C ; tape buffer. The pointer into this buffer can be found at zBUFPNT.
210:
211: .if CompileComputer >= C64_GENERAL
212: lVIDEORAM := $0400
213: .if .defined(C64JAPAN)
214: lBASICRAM := $1000
215: .else
216: lBASICRAM := $0800
217: .endif
218: .endif
219:
220: lVIDEORAM_SIZE := $03FF
221:
222: .if CompileComputer = VIC20_02
223: zMEMUSS_2 := zC3PO
224: .else
225: zMEMUSS_2 := zMEMUSS
226: .endif