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FIELD UPDATES FOR FLASH BASED ST7 APPLICATIONS USING A PC COMM PORT

7 APPENDEX3: S-RECORDS FORMAT DESCRIPTION

Data Record: 'Stnnaaaadddddddddddddddddddddddddddddddd...cc<cr><lf>'

Field Contents:

S -----ASCII 'S' indicates start of record.

t ------Record type, '1','2','3'=data, '9'=end of file

nn ----Number of bytes in record (including address and checksum). (in ASCII/HEX)

aaaa --Load address of data record. (in ASCII/HEX)

dd ----Actual data bytes in record (two ASCII characters per data byte). (in ASCII/

HEX)

cc ----Checksum of count, address, and data. (in ASCII/HEX)

<cr> -ASCII carriage return character. (0D hex, 13 decimal)

<lf> -ASCII line feed character. (0A hex, 10 decimal)

Note 1: The checksum is computed as the one's complement of the eight bit sum of all values

from 'nn' to the end of data (last 'dd' byte).

Note 2: Count 'nn' is three greater then the number of data bytes in the record, since two

bytes of address and one byte of checksum are included in the count.

Note 3: The end of file record (S9) contains a count of 3 and address of 0000h.