Hitachi NJI-350B - Manual (Page 202)

Chapter 7 Programming
7-1
Chapter 7 Programming
7.1 Memory Size and Memory Assignment
Table 7.1. Lists the programming specifications for the MICRO-EH.
Table 7.1 Programming specifications
No. Item 10/14-point type 23/28-point type
1 Program size 3 k steps (3072 steps)
2 Instruction size 32 bits/1 step
3 Memory specification SRAM Backup with a battery is not possible
since a battery cannot be installed. Backup is possible by installing the
battery.
FLASH Backup using flash memory is possible.
4 Programming language H-series ladder/instruction language
5 Program creation Created with H-series programming devices
6 Program modification During STOP Can be done as desired from the programming devices.
During RUN Can be done using the modify during RUN operation (except control instructions).
Control instructions can be changed with special operations. *1
(When a change is made during RUN, control operation stops while the program
is being modified.).
7 Program protection Programs can only be modified when write is enabled. (The enable status is
automatically controlled by the programming device).
8 Password A password can be set from the programming device (the program cannot be
displayed when setting the password. The programs can be downloaded to the
programming device).
9 Check function A sum check function for the program is always executing. An address check with
the I/O assignment table is executed when RUN operation starts.
10 Program name The program names are set from the programming device and stored along with
the programs.
*1: Refer to the peripheral unit manual for details.
Notes:
• Comment data that has been created with the peripheral unit is not stored in the CPU.
• Save the user programs to a floppy disk or other media for backup.
• If a program exceeding 3072 steps is created by setting 4 K steps in the LADDER EDITOR, no error occurs in the LADDER
EDITOR, but a “writing outside memory range” error will occur when writing the program to the CPU.
• Unlike the conventional H series, the MICRO-EH series backup user programs in the FLASH memory.
In order to shorten the program transfer time, the user programs are transferred once to the operation execution memory, at which
point the transfer is completed. The backup to the FLASH memory is performed afterward; therefore, be sure to turn off the
power to the main unit after approximately two minutes have passed since the program transfer. If the power is turned off within
two minutes, a user memory error (31H) may occur. Note that the transfer completion to the FLASH memory can be confirmed
by the special internal output (R7EF).