1 /* i2716.c: Intel 2716 EPROM simulator for 8-bit processors
2
3 Copyright (c) 2011, William A. Beech
4
5 Permission is hereby granted, free of charge, to any person obtaining a
6 copy of this software and associated documentation files (the "Software"),
7 to deal in the Software without restriction, including without limitation
8 the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 and/or sell copies of the Software, and to permit persons to whom the
10 Software is furnished to do so, subject to the following conditions:
11
12 The above copyright notice and this permission notice shall be included in
13 all copies or substantial portions of the Software.
14
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 WILLIAM A. BEECH BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
19 IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
20 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21
22 Except as contained in this notice, the name of William A. Beech shall not be
23 used in advertising or otherwise to promote the sale, use or other dealings
24 in this Software without prior written authorization from William A. Beech.
25
26 These functions support a simulated 2704 to 2764 EPROMs device on an 8-bit
27 computer system. This device allows the attachment of the device to a binary file
28 containing the EPROM code.
29
30 These functions support emulation of 0 to 4 2716 EPROM devices on a CPU board.
31 The byte get and put routines use an offset into the boot EPROM image to locate
32 the proper byte. This allows another device to set the base address for each
33 EPROM.
34
35 This device uses a dynamically allocated buffer to hold each EPROM image.
36 A call to BOOTROM_config will free the current buffer. A call to
37 i2716_reset will allocate a new buffer of 2048 bytes. A
38 call to BOOTROM_attach will load the buffer with the EPROM image.
39 */
40
41 #include <stdio.h>
42 #include "swtp_defs.h"
43
44 #define I2716_NUM 4 /* number of 2716 EPROMS */
45
46 extern int32 get_base(void);
47
48 /* function prototypes */
49
50 t_stat i2716_attach (UNIT *uptr, char *cptr);
51 t_stat i2716_reset (DEVICE *dptr);
52 int32 i2716_get_mbyte(int32 offset);
53
54 /* SIMH EPROM Standard I/O Data Structures */
55
56 UNIT i2716_unit[] = {
57 { UDATA (NULL,UNIT_ATTABLE+UNIT_ROABLE+UNIT_RO, 0), 0 },
58 { UDATA (NULL,UNIT_ATTABLE+UNIT_ROABLE+UNIT_RO, 0), 0 },
59 { UDATA (NULL,UNIT_ATTABLE+UNIT_ROABLE+UNIT_RO, 0), 0 },
60 { UDATA (NULL,UNIT_ATTABLE+UNIT_ROABLE+UNIT_RO, 0), 0 }
61 };
62
63 MTAB i2716_mod[] = {
64 { 0 }
65 };
66
67 DEBTAB i2716_debug[] = {
68 { "ALL", DEBUG_all },
69 { "FLOW", DEBUG_flow },
70 { "READ", DEBUG_read },
71 { "WRITE", DEBUG_write },
72 { "LEV1", DEBUG_level1 },
73 { "LEV2", DEBUG_level2 },
74 { NULL }
75 };
76
77 DEVICE i2716_dev = {
78 "I2716", /* name */
79 i2716_unit, /* units */
80 NULL, /* registers */
81 i2716_mod, /* modifiers */
82 I2716_NUM, /* numunits */
83 16, /* aradix */
84 32, /* awidth */
85 1, /* aincr */
86 16, /* dradix */
87 8, /* dwidth */
88 NULL, /* examine */
89 NULL, /* deposit */
90 &i2716_reset, /* reset */
91 NULL, /* boot */
92 &i2716_attach, /* attach */
93 NULL, /* detach */
94 NULL, /* ctxt */
95 DEV_DEBUG, /* flags */
96 0, /* dctrl */
97 i2716_debug, /* debflags */
98 NULL, /* msize */
99 NULL /* lname */
100 };
101
102 /* global variables */
103
104 /* i2716_attach - attach file to EPROM unit
105 force EPROM reset at completion */
106
i2716_attach(UNIT * uptr,char * cptr)107 t_stat i2716_attach (UNIT *uptr, char *cptr)
108 {
109 int32 j, c;
110 t_stat r;
111 FILE *fp;
112
113 if (i2716_dev.dctrl & DEBUG_flow)
114 printf("i2716_attach: cptr=%s\n", cptr);
115 if ((r = attach_unit (uptr, cptr)) != SCPE_OK) {
116 if (i2716_dev.dctrl & DEBUG_flow)
117 printf("i2716_attach: Error\n");
118 return r;
119 }
120 if (i2716_dev.dctrl & DEBUG_read)
121 printf("\tOpen file\n");
122 fp = fopen(uptr->filename, "rb"); /* open EPROM file */
123 if (fp == NULL) {
124 printf("i2716%d: Unable to open ROM file %s\n", uptr - i2716_dev.units, uptr->filename);
125 printf("\tNo ROM image loaded!!!\n");
126 return SCPE_OK;
127 }
128 if (i2716_dev.dctrl & DEBUG_read)
129 printf("\tRead file\n");
130 j = 0; /* load EPROM file */
131 c = fgetc(fp);
132 while (c != EOF) {
133 *(uint8 *)(uptr->filebuf + j++) = c & 0xFF;
134 c = fgetc(fp);
135 if (j > 2048) {
136 printf("\tImage is too large - Load truncated!!!\n");
137 break;
138 }
139 }
140 if (i2716_dev.dctrl & DEBUG_read)
141 printf("\tClose file\n");
142 fclose(fp);
143 // printf("i2716%d: %d bytes of ROM image %s loaded\n",uptr - i2716_dev.units, j, uptr->filename);
144 if (i2716_dev.dctrl & DEBUG_flow)
145 printf("i2716_attach: Done\n");
146 return SCPE_OK;
147 }
148
149 /* EPROM reset */
150
i2716_reset(DEVICE * dptr)151 t_stat i2716_reset (DEVICE *dptr)
152 {
153 int32 i, j, c, base;
154 t_stat r;
155 UNIT *uptr;
156
157 if (i2716_dev.dctrl & DEBUG_flow)
158 printf("i2716_reset: \n");
159 for (i = 0; i < I2716_NUM; i++) { /* init all units */
160 uptr = i2716_dev.units + i;
161 if (i2716_dev.dctrl & DEBUG_flow)
162 printf("i2716 %d unit.flags=%08X\n", i, uptr->flags);
163 uptr->capac = 2048;
164 uptr->u3 = 2048 * i;
165 base = get_base();
166 if (uptr->filebuf == NULL) { /* no buffer allocated */
167 uptr->filebuf = malloc(2048); /* allocate EPROM buffer */
168 if (uptr->filebuf == NULL) {
169 if (i2716_dev.dctrl & DEBUG_flow)
170 printf("i2716_reset: Malloc error\n");
171 return SCPE_MEM;
172 }
173 }
174 if (base == 0) {
175 // printf("i2716%d: Not enabled on MP-A2\n", i);
176 continue;
177 }
178 // printf("i2716%d: Initializing [%04X-%04XH]\n",
179 // i, base+uptr->u3, base+uptr->u3 + uptr->capac);
180 // if ((uptr->flags & UNIT_ATT) == 0) {
181 // printf("i2716%d: No file attached\n", i);
182 // }
183 }
184 if (i2716_dev.dctrl & DEBUG_flow)
185 printf("i2716_reset: Done\n");
186 return SCPE_OK;
187 }
188
189 /* I/O instruction handlers, called from the CPU module when an
190 EPROM memory read or write is issued.
191 */
192
193 /* get a byte from memory */
194
i2716_get_mbyte(int32 offset)195 int32 i2716_get_mbyte(int32 offset)
196 {
197 int32 i, val, org, len;
198 UNIT *uptr;
199
200 for (i = 0; i < I2716_NUM; i++) { /* find addressed unit */
201 uptr = i2716_dev.units + i;
202 org = uptr->u3;
203 len = uptr->capac - 1;
204 if ((offset >= org) && (offset < (org + len))) {
205 if (uptr->filebuf == NULL) {
206 if (i2716_dev.dctrl & DEBUG_read)
207 printf("i2716_get_mbyte: EPROM not configured\n");
208 return 0xFF;
209 } else {
210 val = *(uint8 *)(uptr->filebuf + (offset - org));
211 if (i2716_dev.dctrl & DEBUG_read)
212 printf(" val=%04X\n", val);
213 return (val & 0xFF);
214 }
215 }
216 }
217 if (i2716_dev.dctrl & DEBUG_read)
218 printf("i2716_get_mbyte: Out of range\n");
219 return 0xFF;
220 }
221
222 /* end of i2716.c */
223