1srec_intel(5) File Formats Manual srec_intel(5)
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6 srec_intel - Intel Hexadecimal object file format specification
7
9 This format is also known as the Intel MCS-86 Object format.
10 This document describes the hexadecimal object file format for the
12 Intel 8-bit, 16-bit, and 32-bit microprocessors. The hexadecimal for‐
13 mat is suitable as input to PROM programmers or hardware emulators.
14 Hexadecimal object file format is a way of representing an absolute
16 binary object file in ASCII. Because the file is in ASCII instead of
17 binary, it is possible to store the file is non-binary medium such as
18 paper-tape, punch cards, etc.; and the file can also be displayed on
19 CRT terminals, line printers, etc.. The 8-bit hexadecimal object file
20 format allows for the placement of code and data within the 16-bit lin‐
21 ear address space of the Intel 8-bit processors. The 16-bit hexadeci‐
22 mal format allows for the 20-bit segmented address space of the Intel
23 16-bit processors. And the 32-bit format allows for the 32-bit linear
24 address space of the Intel 32-bit processors.
25 The hexadecimal representation of binary is coded in ASCII alphanumeric
27 characters. For example, the 8-bit binary value 0011-1111 is 3F in
28 hexadecimal. To code this in ASCII, one 8-bit byte containing the
29 ASCII code for the character '3' (0011-0011 or 0x33) and one 8-bit byte
30 containing the) ASCII code for the character 'F' (0100-0110 or 0x46)
31 are required. For each byte value, the high-order hexadecimal digit is
32 always the first digit of the pair of hexadecimal digits. This repre‐
33 sentation (ASCII hexadecimal) requires twice as many bytes as the
34 binary representation.
35 A hexadecimal object file is blocked into records, each of which con‐
37 tains the record type, length, memory load address and checksum in
38 addition to the data. There are currently six (6) different types of
39 records that are defined, not all combinations of these records are
40 meaningful, however. The record are:
41 · Data Record (8-, 16-, or 32-bit formats)
43 · End of File Record (8-, 16-, or 32-bit formats)
45 · Extended Segment Address Record (16- or 32-bit formats)
47 · Start Segment Address Record (16- or 32-bit formats)
49 · Extended Linear Address Record (32-bit format only)
51 · Start Linear Address Record (32-bit format only)
53 General Record Format
55 ┌───────┬────────┬────────┬────────┬──────┬──────────┐
56 │Record │ Record │ Load │ Record │ Data │ Checksum │
57 │Mark │ Length │ Offset │ Type │ │ │
58 └───────┴────────┴────────┴────────┴──────┴──────────┘
59 Record Mark.
60 Each record begins with a Record Mark field containing 0x3A,
61 the ASCII code for the colon (``:'') character.
62 Record Length
64 Each record has a Record Length field which specifies the num‐
65 ber of bytes of information or data which follows the Record
66 Type field of the record. This field is one byte, represented
67 as two hexadecimal characters. The maximum value of the Record
68 Length field is hexadecimal 'FF' or 255.
69 Load Offset
71 Each record has a Load Offset field which specifies the 16-bit
72 starting load offset of the data bytes, therefore this field is
73 only used for Data Records. In other records where this field
74 is not used, it should be coded as four ASCII zero characters
75 (``0000'' or 0x30303030). This field is two byte, represented
76 as four hexadecimal characters.
77 Record Type
79 Each record has a Record Type field which specifies the record
80 type of this record. The Record Type field is used to inter‐
81 pret the remaining information within the record. This field
82 is one byte, represented as two hexadecimal characters. The
83 encoding for all the current record types are:
84 0 Data Record
86 1 End of File Record
88 2 Extended Segment Address Record
90 3 Start Segment Address Record
92 4 Extended Linear Address Record
94 5 Start Linear Address Record
96 Data Each record has a variable length Data field, it consists of
98 zero or more bytes encoded as pairs of hexadecimal digits. The
99 interpretation of this field depends on the Record Type field.
100 Checksum
102 Each record ends with a Checksum field that contains the ASCII
103 hexadecimal representation of the two's complement of the
104 8-bit bytes that result from converting each pair of ASCII
105 hexadecimal digits to one byte of binary, from and including
106 the Record Length field to and including the last byte of the
107 Data field. Therefore, the sum of all the ASCII pairs in a
108 record after converting to binary, from the Record Length field
109 to and including the Checksum field, is zero.
110 Extended Linear Address Record
112 (32-bit format only)
113 ┌────────┬────────┬────────┬────────┬───────────┬──────────┐
115 │Record │ Record │ Load │ Record │ ULBA │ Checksum │
116 │Mark │ Length │ Offset │ Type │ (2 bytes) │ │
117 │(``:'') │ (2) │ (0) │ (4) │ │ │
118 └T─h─e──3─2─-─b─i┴t──E─x─t─e─n─d─e┴d──L─i─n─e─a─r─┴A─d─d─r─e─s─s──R┴e─c─o─r─d──i─s──u─s─e┴d──t─o──s─p─e─c─i─f┘y bits 16-31
119 of the Linear Base Address (LBA), where bits 0-15 of the LBA are zero.
120 Bits 16-31 of the LBA are referred to as the Upper Linear Base Address
121 (ULBA). The absolute memory address of a content byte in a subsequent
122 Data Record is) obtained by adding the LBA to an offset calculated by
123 adding the Load Offset field of the containing Data Record to the index
124 of the byte in the Data Record (0, 1, 2, ... n). This offset addition
125 is done) modulo 4G (i.e. 32-bits from 0xFFFFFFFF to 0x00000000) results
126 in wrapping around from the end to the beginning of the 4G linear
127 address defined by the LBA. The linear address at which a particular
128 byte is loaded is calculated as:
129 (LBA + DRLO + DRI) MOD 4G
130 where:
131 DRLO is the Load Offset field of a Data Record.
133 DRI is the data byte index within the Data Record.
135 When an Extended Linear Address Record defines the value of LBA, it may
136 appear anywhere within a 32-bit hexadecimal object file. This value
137 remains in effect until another Extended Linear Address Record is
138 encountered. The LBA defaults to zero until an Extended Linear Address
139 Record is encountered. The contents of the individual fields within
140 the record are:
141 Record Mark
143 This field contains 0x3A, the hexadecimal encoding of the ASCII
144 colon (``:'') character.
145 Record Length
147 The field contains 0x3032, the hexadecimal encoding of the
148 ASCII characters ``02'', which is the length, in bytes, of the
149 ULBA data information within this record.
150 Load Offset
152 This field contains 0x30303030, the hexadecimal encoding of the
153 ASCII characters ``0000'', since this field is not used for
154 this record.
155 Record Type
157 This field contains 0x3034, the hexadecimal encoding of the
158 ASCII character ``04'', which specifies the record type to be
159 an Extended Linear Address Record.
160 ULBA This field contains four ASCII hexadecimal digits that specify
162 the 16-bit Upper Linear Base Address value. The value is
163 encoded big-endian (most significant digit first).
164 Checksum
166 This field contains the check sum on the Record Length, Load
167 Offset, Record Type, and ULBA fields.
168 Extended Segment Address Record
170 (16- or 32-bit formats)
171 ┌────────┬────────┬────────┬────────┬───────────┬──────────┐
173 │Record │ Record │ Load │ Record │ USBA │ Checksum │
174 │Mark │ Length │ Offset │ Type │ (2 bytes) │ │
175 │(``:'') │ (2) │ (0) │ (2) │ │ │
176 └T─h─e──1─6─-─b─i┴t──E─x─t─e─n─d─e┴d──S─e─g─m─e─n─t┴─A─d─d─r─e─s─s─┴R─e─c─o─r─d──i─s──u─s┴e─d──t─o──s─p─e─c─i┘fy bits 4-19
177 of the Segment Base Address (SBA), where bits 0-3 of the SBA are zero.
178 Bits 4-19 of the SBA are referred to as the Upper Segment Base Address
179 (USBA). The absolute memory address of a content byte in a subsequent
180 Data Record is) obtained by adding the SBA to an offset calculated by
181 adding the Load Offset field of the containing Data Record to the index
182 of the byte in the Data Record (0, 1, 2, ... n). This offset addition
183 is done modulo 64K (i.e. 16-bits from 0xFFFF to 0x0000 results in wrap‐
184 ping around from the end to the beginning of the 64K segment defined by
185 the SBA. The address at which a particular byte is loaded is calcu‐
186 lated as:
187 SBA + ((DRLO + DRI) MOD 64K)
188 where:
189 DRLO is the LOAD OFFSET field of a Data Record.
191 DRI is the data byte index within the Data Record.
193 When an Extended Segment Address Record defines the value of SBA, it
195 may appear anywhere within a 16-bit hexadecimal object file. This
196 value remains in effect until another Extended Segment Address Record
197 is encountered. The SBA defaults to zero until an Extended Segment
198 Address Record is encountered.
199 The contents of the individual fields within the record are:
201 Record Mark
203 This field contains 0x3A, the hexadecimal encoding of the ASCII
204 colon (``:'') character.
205 Record Length
207 The field contains 0x3032, the hexadecimal encoding of the
208 ASCII characters '02', which is the length, in bytes, of the
209 USBA data information within this record.
210 Load Offset
212 This field contains 0x30303030, the hexadecimal encoding of the
213 ASCII characters '0000', since this field is not used for this
214 record.
215 Record Type
217 This field contains 0x3032, the hexadecimal encoding of the
218 ASCII character ``02'', which specifies the record type to be
219 an Extended Segment Address Record.
220 USBA This field contains four ASCII hexadecimal digits that specify
222 the 16-bit Upper Segment Base Address value. The field is
223 encoded big-endian (most significant digit first).
224 Checksum
226 This field contains the check sum on the Record length, Load
227 Offset, Record Type, and USBA fields.
228 Data Record
230 (8-, 16- or 32-bit formats)
231 ┌────────┬────────┬────────┬────────┬──────┬──────────┐
233 │Record │ Record │ Load │ Record │ Data │ Checksum │
234 │Mark │ Length │ Offset │ Type │ │ │
235 │(``:'') │ │ │ │ │ │
236 └T─h─e──D─a─t─a─┴R─e─c─o─r─d──p─r┴o─v─i─d─e─s──a─┴s─e─t──o─f──h─e┴x─a─d─e─c─i─m┴a─l──d─i─g─i─t─s──t┘hat represent the
237 ASCII code for data bytes that make up a portion of a memory image.
238 The method for calculating the absolute address (linear in the 8-bit
239 and 32-bit case and segmented in the 16-bit case) for each byte of data
240 is described in the discussions of the Extended Linear Address Record
241 and the Extended Segment Address Record.
242 The contents of the individual fields within the record are:
244 Record Mark
246 This field contains 0x3A, the hexadecimal encoding of the ASCII
247 colon (``:'') character.
248 Record Length
250 The field contains two ASCII hexadecimal digits that specify
251 the number of data bytes in the record. The maximum value is
252 255 decimal.
253 Load Offset
255 This field contains four ASCII hexadecimal digits representing
256 the offset from the LBA (see Extended Linear Address Record see
257 Extended Segment Address Record) defining the address which the
258 first byte of the data is to be placed.
259 Record Type
261 This field contains 0x3030, the hexadecimal encoding of the
262 ASCII character ``00'', which specifies the record type to be a
263 Data Record.
264 Data This field contains pairs of ASCII hexadecimal digits, one pair
266 for each data byte.
267 Checksum
269 This field contains the check sum on the Record Length, Load
270 Offset, Record Type, and Data fields.
271 Start Linear Address Record
273 (32-bit format only)
274 ┌────────┬────────┬────────┬────────┬───────────┬──────────┐
276 │Record │ Record │ Load │ Record │ EIP │ Checksum │
277 │Mark │ Length │ Offset │ Type │ (4 bytes) │ │
278 │(``:'') │ (4) │ (0) │ (5) │ │ │
279 └T─h─e──S─t─a─r─t┴─L─i─n─e─a─r──A┴d─d─r─e─s─s──R─e┴c─o─r─d──i─s──u┴s─e─d──t─o──s─p─e─c─i┴f─y──t─h─e──e─x─e─c┘ution start
280 address for the object file. The value given is the 32-bit linear
281 address for the EIP register. Note that this record only specifies the
282 code address within the 32-bit linear address space of the 80386. If
283 the code is to start execution in the real mode of the 80386, then the
284 Start Segment Address Record should be used instead, since that record
285 specifies both the CS and IP register contents necessary for real mode.
286 The Start Linear Address Record can appear anywhere in a 32-bit hexa‐
288 decimal object file. If such a record is not present in a hexadecimal
289 object file, a loader is free to assign a default start address.
290 The contents of the individual fields within the record are:
292 Record mark
294 This field contains 0x3A, the hexadecimal encoding of the ASCII
295 colon (``:'') character.
296 Record length
298 The field contains 0x3034, the hexadecimal encoding of the
299 ASCII characters ``04'', which is the length, in bytes, of the
300 EIP register content within this record.
301 Load Offset
303 This field contains 0x30303030, the hexadecimal encoding of the
304 ASCII characters ``0000'', since this field is not used for
305 this record.
306 Record Type
308 This field contains 0x3035, the hexadecimal encoding of the
309 ASCII character ``05'', which specifies the record type to be a
310 Start Linear Address Record.
311 EIP This field contains eight ASCII hexadecimal digits that specify
313 the 32-bit EIP register contents. The field is encoded big-
314 endian (most significant digit first).
315 Checksum
317 This field contains the check sum on the Record length, Load
318 Offset, Record Type, and EIP fields.
319 Start Segment Address Record
321 (16- or 32-bit formats)
322 ┌────────┬────────┬────────┬────────┬────────────┬────────────┬──────────┐
324 │Record │ Record │ Load │ Record │ CS (2 │ IP (2 │ Checksum │
325 │Mark │ Length │ Offset │ Type │ bytes) │ bytes) │ │
326 │(``:'') │ (4) │ (0) │ (3) │ │ │ │
327 └T─h─e──S─t─a─r─t┴─S─e─g─m─e─n─t─┴A─d─d─r─e─s─s──R┴e─c─o─r─d──i─s─┴u─s─e─d──t─o──s─p─e─c─i┴f─y──t─h─e──e─x─e─c─u─t┴i─o─n──s─t─a─r─t──┘
328 address for the object file. The value given is the 20-bit segment
329 address for the CS and IP registers. Note that this record only speci‐
330 fies the code address within the 20-bit segmented address space of the
331 8086/80186. The Start Segment Address Record can appear anywhere in a
332 16-bit hexadecimal object file. If such a record is not present in a
333 hexadecimal object file, a loader is free to assign a default start
334 address.
335 The contents of the individual fields within the record are:
337 Record Mark
339 This field contains 0x3A, the hexadecimal encoding of the ASCII
340 colon (``:'') character.
341 Record Length
343 The field contains 0x3034, the hexadecimal encoding of the
344 ASCII characters ``04'', which is the length, in bytes, of the
345 CS and IP register contents within this record.
346 Load Offset
348 This field contains 0x30303030, the hexadecimal encoding of the
349 ASCII characters ``0000'', since this field is not used for
350 this record.
351 Record Type
353 This field contains 0x3033, the hexadecimal encoding of the
354 ASCII character '03', which specifies the record type to be a
355 Start Segment Address Record.
356 CS This field contains four ASCII hexadecimal digits that specify
358 the 16-bit CS register contents. The field is encoded big-
359 endian (most significant digit first).
360 IP This field contains four ASCII hexadecimal digits that specify
362 the 16-bit IP register contents. The field is encoded big-
363 endian (most significant digit first).
364 Checksum
366 This field contains the check sum on the Record length, Load
367 Offset, Record Type, CS, and IP fields.
368 End of File Record
370 (8-, 16-, or 32-bit formats)
371 ┌────────┬────────┬────────┬────────┬──────────┐
373 │Record │ Record │ Load │ Record │ Checksum │
374 │Mark │ Length │ Offset │ Type │ (0xFF) │
375 │(``:'') │ (0) │ (0) │ (1) │ │
376 └T─h─e──E─n─d──o┴f──F─i─l─e──R─e┴c─o─r─d──s─p─e─c┴i─f─i─e─s──t─h─e┴──e─n─d───o─f──┘the hexadecimal object
377 file.
378 The contents of the individual fields within the record are:
380 Record mark
382 This field contains 0x3A, the hexadecimal encoding of the ASCII
383 colon (``:'') character.
384 Record Length
386 The field contains 0x3030, the hexadecimal encoding of the
387 ASCII characters ``00''. Since this record does not contain
388 any Data bytes, the length is zero.
389 Load Offset
391 This field contains 0x30303030, the hexadecimal encoding of the
392 ASCII characters ``0000'', since this field is not used for
393 this record.
394 Record Type
396 This field contains 0x3031, the hexadecimal encoding of the
397 ASCII character ``01'', which specifies the record type to be
398 an End of File Record.
399 Checksum
401 This field contains the check sum an the Record Length, Load
402 Offset, and Record Type fields. Since all the fields are
403 static, the check sum can also be calculated statically, and
404 the value is 0x4646, the hexadecimal encoding of the ASCII
405 characters ``FF''.
406 Size Multiplier
408 In general, binary data will expand in sized by approximately 2.3 times
409 when represented with this format.
410
412 Here is an example Intel hex file. It contains the data ``Hello,
413 World'' to be loaded at address 0.
414 :0D00000048656C6C6F2C20576F726C640AA1
415 :00000001FF
416
418 This information comes (very indirectly) from Microprocessors and Pro‐
419 grammed Logic, Second Edition, Kenneth L. Short, 1987, Prentice-Hall,
420 ISBN 0-13-580606-2.
421
423 srec_cat version 1.35
424 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
425 2007 Peter Miller
426 The srec_cat program comes with ABSOLUTELY NO WARRANTY; for details use
428 the 'srec_cat -VERSion License' command. This is free software and you
429 are welcome to redistribute it under certain conditions; for details
430 use the 'srec_cat -VERSion License' command.
431
433 Peter Miller E-Mail: millerp@canb.auug.org.au
434 /\/\* WWW: http://www.canb.auug.org.au/~millerp/
435 Derivation
437 This manual page is derived from a file marked as follows:
438 Intel Hexadecimal Object File Format Specification; Revision A, 1/6/88
440 Disclaimer: Intel makes no representation or warranties with respect to
442 the contents hereof and specifically disclaims any implied warranties
443 of merchantability or fitness for any particular purpose. Further,
444 Intel reserves the right to revise this publication from time to time
445 in the content hereof without obligation of Intel to notify any person
446 of such revision or changes. The publication of this specification
447 should not be construed as a commitment on Intel's part to implement
448 any product.
449Reference Manual SRecord srec_intel(5)