Data I/O 298 Manual page 108

Although each data byte has an address, most are implied.
Data bytes are addressed sequentially unless an explicit
address is included in the data stream. This address is
preceded by a "$" and an "A", must contain 2 to 4 hex or
3 to 6 octal characters, and must be followed by a comma,
except for the ASCII-Hex (Comma) format, which uses a
period. The programmer skips to the new address to store
the next data byte; succeeding bytes are again stored
sequentially. See figure A-6.
ADDRESS
FIELD
HEX
ADDRESS
,------l---~
.~.
:_~~~~~~·-i
OR
OCTAL
ADDRESS
~
r - - .::..:.:::..:..:..-:
$A123456
I
'
'
----------
,-
-
-
- -
-
- - - - -
-
-
- - - -
-
-
-
-
-
- -
-
-
,
:eHHHHHH.... : _
r-: . . . .
HH HH HH HH:
INPUT
DATA
I
!_ ______________________ !
Data byte that follows address
field is input to RAM address
defined in address field.
NOTES:
• H =hex character. 1,2,3,4,5, and 6 = octal characters.
• Address has 2-4 or 3-6 octal characters. The programmer
assumes leading zeros.
• Address must be preceded by "$A" and followed by ", ".
• Line feed and carriage return optional.
• The most significant octal digit may be 0 or 1 when
expressing 16 bits as 6 octal characters.
Figure A-6. Optional Address Field in ASCII-Octal and
Hex Formats
Each format has an end code, which terminates input
operations. However, if a new start code follows within 16
characters of an end code, input will continue
uninterrupted.
After receiving the final end code following an input
operation, the programmer calculates a sum-check of all
incoming data. Optionally, a sum-check can also be
entered in the input data stream. The programmer
compares this sum-check with its own calculated sum-
check. If they match, the programmer will display the sum-
check; if not, a sum-check error will be displayed.
Specifications for the optional sum-check are given in
figure A-7.
End of Hex Data
I
... HH HH HH
End of Octal Data
I
235 235
NOTES:
[end code]
[end code]
Hex
Sum-Check
I
$SH~HH.'
Octal
Sum-Check
I
$S123456
• Sum-check field consists of 2-4 hex or 3-6 octal digits
sandwiched between "$S" and'',".
• Sum-check field immediately follows end code.
• Sum-check field optional in the input mode and always
included in the output mode.
• The most significant octal digit of the sum-check may be
0 or 1 when expressing 16 bits as 6 octal characters.
Figure A-7. Syntax of the Sum-Check Field in 1/0
Operations ·
Output is begun by invoking an output-to-port operation.
The programmer divides the output data into 8-line blocks.
Data transmission is begun with the start code, a
nonprintable STX, optionally SOH.
*
Data blocks follow,
each one prefaced by an address for the first data byte in
the block. The end of transmission is signalled by the end
code, a nonprintable ETX. Directly following the end code
is a sum-check of the transferred data.
*
ASCII-Octal SMS and ASCII-Hex SMS use SOM ICTRL Rl as a
start code and EOM (CTRL Tl as an end code.
A-6
10-990-0013