8
3-3 Communications procedures
3-3-1 Memory Link Commands
Command/response formats are as mentioned below.
•
Read/write/change notify command
ESC command *S
*A
*L
*D
SUM
CR
•
Read/write command (In above-mentioned format, the *L is regarded as
1 (fixed))
ESC command *S
*A
*D
SUM
CR
•
Write all (FILL) command
ESC command *S
*A
*B
*D
SUM
CR
•
Read type command normal completion response format
ESC command *A
*L
*D
SUM
CR
•
Other responses
ESC command *D
SUM
CR
ESC
($1B)
Initial Command: ESC($1B) fixed
command 2
characters
1 English capital letters which display the
type of command
*S 1
character
Designates SUM omission and *L omission. In
some cases, specifies write to memory attributes
as well.
SUM OFF: SUM computing by host can be omitted.
SUM ON: enables judgment if command is invalid
as a result of noise interference.
*A
Hexadecimal
4 digits
Initial read/write address
*B
Hexadecimal
4 digits
Last Write all (FILL) address
*L
BCD 2 digits
Number of read/write elements
*D
Variable length
Data section
SUM
2 characters
(may be
abbreviated)
The checksum of the command response is the 2
digit code in hexadecimal which is indicated using
lower one-byte of the total sum from the ESC to
