Appendix B Task Codes Specifications
Task code
H20
Clear all
Classification
Memory write
Function
Clear the designated area in the user memory.
Execution condition
CPU
status
STOP RUN HALT
ERROR
×
×
×
×
READ occupancy
Occupancy
{
×
×
{
WRITE occupancy
status
Format
Request
H20
(a)
(a) Function selection (subcommand)
1]
H00: Initialization of all user memory area
2]
H01: Initialization of the HI-FLOW area *1
3]
H02: Initialization of the HI-LADDER area
4]
H03: Zero clear of all user memory area
*1: EH-150 does not support HI-FLOW.
Response
(a)
H20
(a) Response task code (H00 when executed normally)
For task codes other than the normal task codes, refer to the “response
list by task code” at the end of this chapter.
Description
(1) The composition of user memory
The user memory has the composition as shown
in the diagram to the right. Parameter area (A)
stores the I/O assignment, memory assignment
and other information, while parameter area (B)
stores the timer information, etc.
Parameter area
Parameter area (A)
Parameter area (B)
HI-FLOW area
HI-LADDER area
User memory
(2) Description of each function
1]
Initialization of all user memory areas (subcommand H00)
Initializes all of parameter areas (A) and (B), the HI-FLOW area and the HI-LADDER area. If this command is
executed, memory are assigned as follows. Also, the I/O assignment is erased.
Assignment
capacity
Parameter area ((A), (B) total)
:
H0280
HI-FLOW area
:
H0000
HI-LADDER area
:
Load capacity *2 – H0280
*2 : Determine the load capacity from H10 “CPU status 2] user memory capacity”.
B-18
