S3C44B0X

Manufacturer Part NumberS3C44B0X
DescriptionBGA
ManufacturerSamsung
S3C44B0X datasheets
 

Specifications of S3C44B0X

Date_code02+  
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
Page 91
92
Page 92
93
Page 93
94
Page 94
95
Page 95
96
Page 96
97
Page 97
98
Page 98
99
Page 99
100
Page 100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
Page 97/488

Download datasheet (3Mb)Embed
PrevNext
ARM INSTRUCTION SET
INCLUSION OF THE BASE IN THE REGISTER LIST
When write-back is specified, the base is written back at the end of the second cycle of the instruction. During a
STM, the first register is written out at the start of the second cycle. A STM which includes storing the base, with the
base as the first register to be stored, will therefore store the unchanged value, whereas with the base second or
later in the transfer order, will store the modified value. A LDM will always overwrite the updated base if the base is in
the list.
DATA ABORTS
Some legal addresses may be unacceptable to a memory management system, and the memory manager can
indicate a problem with an address by taking the ABORT signal HIGH. This can happen on any transfer during a
multiple register load or store, and must be recoverable if ARM920T is to be used in a virtual memory system.
Abort during STM Instructions
If the abort occurs during a store multiple instruction, ARM920T takes little action until the instruction completes,
whereupon it enters the data abort trap. The memory manager is responsible for preventing erroneous writes to the
memory. The only change to the internal state of the processor will be the modification of the base register if write-
back was specified, and this must be reversed by software (and the cause of the abort resolved) before the
instruction may be retried.
Aborts during LDM Instructions
When ARM920T detects a data abort during a load multiple instruction, it modifies the operation of the instruction to
ensure that recovery is possible.
Overwriting of registers stops when the abort happens. The aborting load will not take place but earlier ones may
have overwritten registers. The PC is always the last register to be written and so will always be preserved.
The base register is restored, to its modified value if write-back was requested. This ensures recoverability in the
case where the base register is also in the transfer list, and may have been overwritten before the abort occurred.
The data abort trap is taken when the load multiple has completed, and the system software must undo any base
modification (and resolve the cause of the abort) before restarting the instruction.
INSTRUCTION CYCLE TIMES
Normal LDM instructions take nS + 1N + 1I and LDM PC takes (n+1)S + 2N + 1I incremental cycles, where S,N and
I are defined as sequential (S-cycle), non-sequential (N-cycle), and internal (I-cycle), respectively. STM instructions
take (n-1)S + 2N incremental cycles to execute, where n is the number of words transferred.
3-44
S3C2400 RISC MICROPROCESSOR