OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [rtos/] [ecos-2.0/] [doc/] [html/] [ref/] [io-user-api.html] - Blame information for rev 174

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 28 unneback
<!-- Copyright (C) 2003 Red Hat, Inc.                                -->
2
<!-- This material may be distributed only subject to the terms      -->
3
<!-- and conditions set forth in the Open Publication License, v1.0  -->
4
<!-- or later (the latest version is presently available at          -->
5
<!-- http://www.opencontent.org/openpub/).                           -->
6
<!-- Distribution of the work or derivative of the work in any       -->
7
<!-- standard (paper) book form is prohibited unless prior           -->
8
<!-- permission is obtained from the copyright holder.               -->
9
<HTML
10
><HEAD
11
><TITLE
12
>User API</TITLE
13
><meta name="MSSmartTagsPreventParsing" content="TRUE">
14
<META
15
NAME="GENERATOR"
16
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
17
"><LINK
18
REL="HOME"
19
TITLE="eCos Reference Manual"
20
HREF="ecos-ref.html"><LINK
21
REL="UP"
22
TITLE="I/O Package (Device Drivers)"
23
HREF="io.html"><LINK
24
REL="PREVIOUS"
25
TITLE="Introduction"
26
HREF="io-package-intro.html"><LINK
27
REL="NEXT"
28
TITLE="Serial driver details"
29
HREF="io-serial-driver-details.html"></HEAD
30
><BODY
31
CLASS="CHAPTER"
32
BGCOLOR="#FFFFFF"
33
TEXT="#000000"
34
LINK="#0000FF"
35
VLINK="#840084"
36
ALINK="#0000FF"
37
><DIV
38
CLASS="NAVHEADER"
39
><TABLE
40
SUMMARY="Header navigation table"
41
WIDTH="100%"
42
BORDER="0"
43
CELLPADDING="0"
44
CELLSPACING="0"
45
><TR
46
><TH
47
COLSPAN="3"
48
ALIGN="center"
49
>eCos Reference Manual</TH
50
></TR
51
><TR
52
><TD
53
WIDTH="10%"
54
ALIGN="left"
55
VALIGN="bottom"
56
><A
57
HREF="io-package-intro.html"
58
ACCESSKEY="P"
59
>Prev</A
60
></TD
61
><TD
62
WIDTH="80%"
63
ALIGN="center"
64
VALIGN="bottom"
65
></TD
66
><TD
67
WIDTH="10%"
68
ALIGN="right"
69
VALIGN="bottom"
70
><A
71
HREF="io-serial-driver-details.html"
72
ACCESSKEY="N"
73
>Next</A
74
></TD
75
></TR
76
></TABLE
77
><HR
78
ALIGN="LEFT"
79
WIDTH="100%"></DIV
80
><DIV
81
CLASS="CHAPTER"
82
><H1
83
><A
84
NAME="IO-USER-API">Chapter 15. User API</H1
85
><P
86
>All functions, except <TT
87
CLASS="FUNCTION"
88
>cyg_io_lookup()</TT
89
>
90
require an I/O &#8220;handle&#8221;.</P
91
><P
92
>All functions return a value of the type <SPAN
93
CLASS="TYPE"
94
>Cyg_ErrNo</SPAN
95
>. If an
96
error condition is detected, this value will be negative and the
97
absolute value indicates the actual error, as specified in
98
<TT
99
CLASS="FILENAME"
100
>cyg/error/codes.h</TT
101
>. The only other legal return
102
value will be <TT
103
CLASS="VARNAME"
104
>ENOERR</TT
105
>. All other function arguments
106
are pointers (references). This allows the drivers to pass information
107
efficiently, both into and out of the driver. The most striking
108
example of this is the &#8220;length&#8221; value passed to the read
109
and write functions. This parameter contains the desired length of
110
data on input to the function and the actual transferred length on
111
return.</P
112
><TABLE
113
BORDER="5"
114
BGCOLOR="#E0E0F0"
115
WIDTH="70%"
116
><TR
117
><TD
118
><PRE
119
CLASS="PROGRAMLISTING"
120
>// Lookup a device and return its handle
121
  Cyg_ErrNo <TT
122
CLASS="FUNCTION"
123
>cyg_io_lookup</TT
124
>(
125
    const char <TT
126
CLASS="PARAMETER"
127
><I
128
>*name</I
129
></TT
130
>,
131
    cyg_io_handle_t <TT
132
CLASS="PARAMETER"
133
><I
134
>*handle</I
135
></TT
136
> )</PRE
137
></TD
138
></TR
139
></TABLE
140
><P
141
>This function maps a device name onto an appropriate handle. If the
142
named device is not in the system, then the error
143
<TT
144
CLASS="VARNAME"
145
>-ENOENT</TT
146
> is returned. If the device is found, then
147
the handle for the device is returned by way of the handle pointer
148
<TT
149
CLASS="PARAMETER"
150
><I
151
>*handle</I
152
></TT
153
>.</P
154
><TABLE
155
BORDER="5"
156
BGCOLOR="#E0E0F0"
157
WIDTH="70%"
158
><TR
159
><TD
160
><PRE
161
CLASS="PROGRAMLISTING"
162
>// Write data to a device
163
Cyg_ErrNo <TT
164
CLASS="FUNCTION"
165
>cyg_io_write</TT
166
>(
167
    cyg_io_handle_t <TT
168
CLASS="PARAMETER"
169
><I
170
>handle</I
171
></TT
172
>,
173
    const void <TT
174
CLASS="PARAMETER"
175
><I
176
>*buf</I
177
></TT
178
>,
179
    cyg_uint32 <TT
180
CLASS="PARAMETER"
181
><I
182
>*len</I
183
></TT
184
> )</PRE
185
></TD
186
></TR
187
></TABLE
188
><P
189
>This function sends data to a device. The size of data to send is
190
contained in <TT
191
CLASS="PARAMETER"
192
><I
193
>*len</I
194
></TT
195
> and the actual size sent will
196
be returned in the same place.</P
197
><TABLE
198
BORDER="5"
199
BGCOLOR="#E0E0F0"
200
WIDTH="70%"
201
><TR
202
><TD
203
><PRE
204
CLASS="PROGRAMLISTING"
205
>// Read data from a device
206
Cyg_ErrNo <TT
207
CLASS="FUNCTION"
208
>cyg_io_read</TT
209
>(
210
    cyg_io_handle_t <TT
211
CLASS="PARAMETER"
212
><I
213
>handle</I
214
></TT
215
>,
216
    void <TT
217
CLASS="PARAMETER"
218
><I
219
>*buf</I
220
></TT
221
>,
222
    cyg_uint32 <TT
223
CLASS="PARAMETER"
224
><I
225
>*len</I
226
></TT
227
> )</PRE
228
></TD
229
></TR
230
></TABLE
231
><P
232
>This function receives data from a device. The desired size of data to
233
receive is contained in <TT
234
CLASS="PARAMETER"
235
><I
236
>*len</I
237
></TT
238
> and the actual
239
size obtained will be returned in the same place.</P
240
><TABLE
241
BORDER="5"
242
BGCOLOR="#E0E0F0"
243
WIDTH="70%"
244
><TR
245
><TD
246
><PRE
247
CLASS="PROGRAMLISTING"
248
>// Get the configuration of a device
249
Cyg_ErrNo <TT
250
CLASS="FUNCTION"
251
>cyg_io_get_config</TT
252
>(
253
    cyg_io_handle_t <TT
254
CLASS="PARAMETER"
255
><I
256
>handle</I
257
></TT
258
>,
259
    cyg_uint32 <TT
260
CLASS="PARAMETER"
261
><I
262
>key</I
263
></TT
264
>,
265
    void *<TT
266
CLASS="PARAMETER"
267
><I
268
>buf</I
269
></TT
270
>,
271
    cyg_uint32 *<TT
272
CLASS="PARAMETER"
273
><I
274
>len</I
275
></TT
276
> )</PRE
277
></TD
278
></TR
279
></TABLE
280
><P
281
>This function is used to obtain run-time configuration about a
282
device. The type of information retrieved is specified by the
283
<TT
284
CLASS="PARAMETER"
285
><I
286
>key</I
287
></TT
288
>. The data will be returned in the given
289
buffer. The value of <TT
290
CLASS="PARAMETER"
291
><I
292
>*len</I
293
></TT
294
> should contain the
295
amount of data requested, which must be at least as large as the size
296
appropriate to the selected key. The actual size of data retrieved is
297
placed in <TT
298
CLASS="PARAMETER"
299
><I
300
> *len</I
301
></TT
302
>. The appropriate key values
303
differ for each driver and are all listed in the file
304
<TT
305
CLASS="FILENAME"
306
>&lt;cyg/io/config_keys.h&gt;</TT
307
>.</P
308
><TABLE
309
BORDER="5"
310
BGCOLOR="#E0E0F0"
311
WIDTH="70%"
312
><TR
313
><TD
314
><PRE
315
CLASS="PROGRAMLISTING"
316
>// Change the configuration of a device
317
Cyg_ErrNo <TT
318
CLASS="FUNCTION"
319
>cyg_io_set_config</TT
320
>(
321
    cyg_io_handle_t <TT
322
CLASS="PARAMETER"
323
><I
324
>handle</I
325
></TT
326
>,
327
    cyg_uint32 <TT
328
CLASS="PARAMETER"
329
><I
330
>key</I
331
></TT
332
>,
333
    const void <TT
334
CLASS="PARAMETER"
335
><I
336
>*buf</I
337
></TT
338
>,
339
    cyg_uint32 <TT
340
CLASS="PARAMETER"
341
><I
342
>*len</I
343
></TT
344
> )</PRE
345
></TD
346
></TR
347
></TABLE
348
><P
349
>This function is used to manipulate or change the run-time
350
configuration of a device. The type of information is specified by the
351
<TT
352
CLASS="PARAMETER"
353
><I
354
>key</I
355
></TT
356
>. The data will be obtained from the given
357
buffer. The value of <TT
358
CLASS="PARAMETER"
359
><I
360
>*len</I
361
></TT
362
> should contain the
363
amount of data provided, which must match the size appropriate to the
364
selected key.  The appropriate key values differ for each driver and
365
are all listed in the file
366
<TT
367
CLASS="FILENAME"
368
>&lt;cyg/io/config_keys.h&gt;</TT
369
>.</P
370
></DIV
371
><DIV
372
CLASS="NAVFOOTER"
373
><HR
374
ALIGN="LEFT"
375
WIDTH="100%"><TABLE
376
SUMMARY="Footer navigation table"
377
WIDTH="100%"
378
BORDER="0"
379
CELLPADDING="0"
380
CELLSPACING="0"
381
><TR
382
><TD
383
WIDTH="33%"
384
ALIGN="left"
385
VALIGN="top"
386
><A
387
HREF="io-package-intro.html"
388
ACCESSKEY="P"
389
>Prev</A
390
></TD
391
><TD
392
WIDTH="34%"
393
ALIGN="center"
394
VALIGN="top"
395
><A
396
HREF="ecos-ref.html"
397
ACCESSKEY="H"
398
>Home</A
399
></TD
400
><TD
401
WIDTH="33%"
402
ALIGN="right"
403
VALIGN="top"
404
><A
405
HREF="io-serial-driver-details.html"
406
ACCESSKEY="N"
407
>Next</A
408
></TD
409
></TR
410
><TR
411
><TD
412
WIDTH="33%"
413
ALIGN="left"
414
VALIGN="top"
415
>Introduction</TD
416
><TD
417
WIDTH="34%"
418
ALIGN="center"
419
VALIGN="top"
420
><A
421
HREF="io.html"
422
ACCESSKEY="U"
423
>Up</A
424
></TD
425
><TD
426
WIDTH="33%"
427
ALIGN="right"
428
VALIGN="top"
429
>Serial driver details</TD
430
></TR
431
></TABLE
432
></DIV
433
></BODY
434
></HTML
435
>

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.