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1.1 root 1: /*
2: Hatari
3:
4: Bios Handler (Trap #13)
5:
6: We intercept and direct some Bios calls to handle input/output to RS-232 or the printer etc...
7: */
8:
9: #include "main.h"
10: #include "debug.h"
11: #include "decode.h"
12: #include "floppy.h"
13: #include "m68000.h"
14: #include "misc.h"
15: #include "printer.h"
16: #include "rs232.h"
17: #include "stMemory.h"
18:
19:
20: /*-----------------------------------------------------------------------*/
21: /*
22: BIOS Return input device status
23: Call 1
24: */
25: BOOL Bios_Bconstat(unsigned long Params)
26: {
27: unsigned short Dev;
28:
29: Dev = STMemory_ReadWord(Params+SIZE_WORD);
30: switch(Dev) {
31: case 0: /* PRT: Centronics */
32: Regs[REG_D0] = 0; /* No characters ready(cannot read from printer) */
33: return(TRUE);
34: case 1: /* AUX: RS-232 */
35: if (RS232_GetStatus())
36: Regs[REG_D0] = -1; /* Chars waiting */
37: else
38: Regs[REG_D0] = 0;
39: return(TRUE);
40: }
41:
42: return(FALSE);
43: }
44:
45: /*-----------------------------------------------------------------------*/
46: /*
47: BIOS Read character from device
48: Call 2
49: */
50: BOOL Bios_Bconin(unsigned long Params)
51: {
52: unsigned short Dev;
53: unsigned char Char;
54:
55: Dev = STMemory_ReadWord(Params+SIZE_WORD);
56: switch(Dev) {
57: case 0: /* PRT: Centronics */
58: Regs[REG_D0] = 0; /* Force NULL character(cannot read from printer) */
59: return(TRUE);
60: case 1: /* AUX: RS-232 */
61: RS232_ReadBytes(&Char,1);
62: Regs[REG_D0] = Char;
63: return(TRUE);
64: }
65:
66: return(FALSE);
67: }
68:
69: /*-----------------------------------------------------------------------*/
70: /*
71: BIOS Write character to device
72: Call 3
73: */
74: BOOL Bios_Bconout(unsigned long Params)
75: {
76: unsigned short Dev;
77: unsigned char Char;
78:
79: Dev = STMemory_ReadWord(Params+SIZE_WORD);
80: Char = STMemory_ReadWord(Params+SIZE_WORD+SIZE_WORD);
81: switch(Dev) {
82: case 0: /* PRT: Centronics */
83: Printer_TransferByteTo(Char);
84: return(TRUE);
85: case 1: /* AUX: RS-232 */
86: RS232_TransferBytesTo(&Char,1);
87: return(TRUE);
88: }
89:
90: return(FALSE);
91: }
92:
93: /*-----------------------------------------------------------------------*/
94: /*
95: BIOS Read/Write disc sector
96: Call 4
97: */
98: BOOL Bios_RWabs(unsigned long Params)
99: {
100: #ifdef DEBUG_TO_FILE
101: char *pBuffer;
102: unsigned short int RWFlag,Number,RecNo,Dev;
103:
104: /* Read details from stack */
105: RWFlag = STMemory_ReadWord(Params+SIZE_WORD);
106: pBuffer = (char *)STMemory_ReadLong(Params+SIZE_WORD+SIZE_WORD);
107: Number = STMemory_ReadWord(Params+SIZE_WORD+SIZE_WORD+SIZE_LONG);
108: RecNo = STMemory_ReadWord(Params+SIZE_WORD+SIZE_WORD+SIZE_LONG+SIZE_WORD);
109: Dev = STMemory_ReadWord(Params+SIZE_WORD+SIZE_WORD+SIZE_LONG+SIZE_WORD+SIZE_WORD);
110:
111: Debug_FDC("RWABS %s,%d,0x%X,%d,%d\n",EmulationDrives[Dev].szFileName,RWFlag,(char *)STRAM_ADDR(pBuffer),RecNo,Number);
112: #endif
113:
114: return(FALSE);
115: }
116:
117: /*-----------------------------------------------------------------------*/
118: /*
119: BIOS Return output device status
120: Call 8
121: */
122: BOOL Bios_Bcostat(unsigned long Params)
123: {
124: unsigned short Dev;
125:
126: Dev = STMemory_ReadWord(Params+SIZE_WORD);
127: switch(Dev) {
128: case 0: /* PRT: Centronics */
129: Regs[REG_D0] = -1; /* Device ready */
130: return(TRUE);
131: case 1: /* AUX: RS-232 */
132: Regs[REG_D0] = -1; /* Device ready */
133: return(TRUE);
134: }
135:
136: return(FALSE);
137: }
138:
139: /*-----------------------------------------------------------------------*/
140: /*
141: BIOS Media change
142: Call 9
143: */
144: BOOL Bios_Mediach(unsigned long Params)
145: {
146: unsigned short int Dev,ImageChanged=0;
147:
148: /* Read details from stack */
149: Dev = STMemory_ReadWord(Params+SIZE_WORD);
150:
151: /* Check we are trying to access a floppy drive? */
152: if (Dev<2) {
153: /* Have we inserted a new disc image into this drive? */
154: if (EmulationDrives[Dev].bMediaChanged) {
155: EmulationDrives[Dev].bMediaChanged = FALSE;
156: ImageChanged = 2; /* We did change disc image */
157: }
158: }
159:
160: /* Set 0 if was not changed or 2 if was */
161: Regs[REG_D0] = ImageChanged;
162:
163: return(TRUE);
164: }
165:
166: /*-----------------------------------------------------------------------*/
167: /*
168: Check Bios call and see if we need to re-direct to our own routines
169: Return TRUE if we've handled the exception, else return FALSE to let TOS attempt it
170: */
171: BOOL Bios(void)
172: {
173: unsigned long Params;
174: unsigned short int BiosCall;
175:
176: /* Get call */
177: Params = Regs[REG_A7];
178: BiosCall = STMemory_ReadWord(Params);
179: // Debug_File("BIOS %d\n",BiosCall);
180:
181: /* Intercept? */
182: switch(BiosCall) {
183: case 0x1:
184: return(Bios_Bconstat(Params));
185: case 0x2:
186: return(Bios_Bconin(Params));
187: case 0x3:
188: return(Bios_Bconout(Params));
189: case 0x4:
190: return(Bios_RWabs(Params));
191: case 0x8:
192: return(Bios_Bcostat(Params));
193: case 0x9:
194: return(Bios_Mediach(Params));
195:
196: default: /* Call as normal! */
197: return(FALSE);
198: }
199: }
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