Hioki 3504-40 C HiTester, Instruction Manual

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8.6 Things to Know before Beginning Communication
147
8
RS-232 reads the status bytes to find out the status of the unit.
The unit adopts the IEEE488.2 defined status model for parts related to the serial
polling performed by the service request function. A trigger for generating a ser-
vice request is called an event.
The event register and output queue information is set in the status byte register.
The service request enable register can be used to further select required items
from this information. If the selected information is set, bit 6 (MMS master sum-
mary status bit) of the status byte register is set and an SRQ (service request)
message is generated and used to generate a service request.
8.6.3 About the Status Byte Register
bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0
Unused
SRQ
ESB MAV ESB3 ESB2 ESB1 ESB0
MSS
& & & & & &
bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0
Unused x ESB MAV ESB3 ESB2 ESB1 ESB0
Logical
OR
Status Byte
Register (STB)
Service Request
Enable Register
(SRER)
Generate a
Service Re-
quest SRQ
Output Queue Data Information
Standard Event Register Information
Conceptual Diagram of Generation of Service Request
Event Register Information for
Each Bit
For RS-232C, bit 4 (MAV message available) of the status byte register is not
set.