4-3
Section
Command Format
33
Command/Response Format
The command sent from the host computer to the ID Controller, and the re-
sponse returned from the ID Controller to the host computer are in the following
format:
X
X
X
X
.........
X
∗
CR
1 frame = 266 characters max.
Header
Text
Terminator
Type
Description
Header
Command
Two-character symbol indicating operation.
Response
Symbol same as header of executed command
Text
Command
Contents of processing:
– ASCII/HEX code specification
– R/W Head no. specification (fixed to 1)
– Processing start address
– Number of bytes to be processed (for read command), write data (for write
command)
Response
Result of processing
– End code
– Read data (for read command)
Terminator
Indicates end of command or response.
Note:
∗
indicates “2A”H of ASCII code, and CR indicates “0D”H.
If the length of an expansion command exceeds 266 characters, or the length of
a response to an expansion command exceeds 256 characters, the command
or response is divided into several frames as follows. At this time, the terminator
(
∗
CR) is appended to the last frame, and a delimiter (CR) is appended to the oth-
er frames.
If response length exceeds 256 characters (for expansion read command):
After transmitting a response which is not the last frame, the ID Controller
transmits the next response frame when it has received a delimiter (CR)
from the host controller.
Command
Response
<Host >
<ID Controller>
Delimiter: CR
T
erminator
T
ext
Header XR
T
ext
Header XR
Delimiter
Delimiter
T
ext
Delimiter
Delimiter
T
erminator
T
ext