Toshiba G7 - Manual (Page 48)

G7 ASD Multi-Protocol Communication Option and PG Feedback Option Manual 41
Scan Register Notes
• Items marked as “RESERVED” in Table 22 are reserved for future use. Selecting one of the
corresponding values as command scan data will have no effect on drive operation.
• Configurable scan register selection parameters F831∼F835 and F841∼F846 are only validated on
drive reset or power-up. Therefore, if any of these parameters are changed, be sure to reset the
drive to validate the changes.
• Data range checking is not performed on command scan items. If a value outside of a specific
item’s valid range is written to the Modbus interface, that value will be accepted by the interface,
but ignored by the drive.
• Command scan data is written to drive RAM only, and therefore not retained when power is lost.
• Initial values for command scan data (before the first network update is received) are 0.
• Basic command (Modbus register 0x0A07) and extended command (Modbus register 0x0A24)
registers: for these command words to have an actual effect on the drive’s operation, either the
drive’s “command mode selection” parameter must be set such that option board commands are
valid, or the “option priority” bit (bit #15) of the basic command word must be set via Modbus
communications.
• Basic command (Modbus register 0x0A07): for a detail of this register, refer to Table 10 on page
23.
• Extended command (Modbus register 0x0A24): for a detail of this register, refer to Table 11 on
page 23.
• Option board frequency command (Modbus register 0x0A08): for this value to have an actual effect
on the drive’s operation, either the drive’s “frequency mode selection” parameter must be set such
that option board frequency command is valid, or the “option priority” bit (bit #14) of the basic
command word must be set via Modbus communications.
10.2.5 Supported Modbus Functions
The Multicom Modbus interface supports three Modbus commands: command 3 (0x03: read holding
registers), command 6 (0x06: preset single register) and command 16 (0x10: preset multiple registers).
Not all drive registers support all commands (for example, certain drive registers may be read-only or
write-only): refer to the
Toshiba Serial Communications Manual for specific details about the various
drive registers. Table 23 indicates the maximum number of registers that can be read/written in one
packet transaction.
Table 23: Read / Write Limits
Command Read Max Write Max
3 125 registers N/A
6 N/A 1 register only
16 N/A 123 registers
Except for scan register writes (refer to Section 10.2.4), all register writes update the drive’s EEPROM.
For this reason, do not write to any single non-scan register more than 10,000 times or EEPROM
damage may occur.