DS2490
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033199
Control Command Set Summary Table 11
Command
RESET DEVICE
START EXECUTION
RESUME EXECUTION
HALT EXECUTION WHEN
IDLE
HALT EXECUTION WHEN
DONE
CANCEL COMMAND
CANCEL MACRO
FLUSH COMM CMDS
Function
Perform a hardware reset.
Start execution of Communication commands.
Resume execution of Communication commands.
Halt Communication command execution when the 1-Wire bus is
idle.
Halt further Communication command execution when the current
command execution completes.
Terminate Communication command execution.
Terminate Communication command macro execution.
Clear unexecuted Communication commands from the command
buffer.
Clear the data receive buffer (data from a 1-Wire device).
Clear the data transmit buffer (data to a 1-Wire device).
Retrieve unexecuted Communication commands from the command
buffer.
FLUSH DATA RCV BUFFER
FLUSH DATA XMT BUFFER
GET COMM CMDS
Control Command Set Descriptions:
RESET DEVICE
–This command performs a hardware reset equivalent to the power-on reset. This
includes clearing all endpoint buffers and loading the Mode control registers with their default values.
START EXECUTION
– This command starts execution of Communication commands. This command
is also required to start the execution of Communication commands with an IM (immediate execution
control) bit set to logic 0.
RESUME EXECUTION
– This command is used to resume execution of a Communication command
that was halted with either of the HALT EXECUTION commands.
HALT EXECUTION WHEN IDLE –
This command is used to halt the execution of the current
Communication command after the 1-Wire bus has returned to the idle state. Further Communication
command processing is stopped until a RESUME EXECUTION command is received. This command,
or the HALT EXECUTION WHEN DONE command, is also used to terminate a strong pullup or
programming pulse of semi-infinite or infinite duration.
HALT EXECUTION WHEN DONE
– This command is used to halt the execution of a
Communication command after the current command execution is complete. Further Communication
command processing is stopped until a RESUME EXECUTION command is received. This command,
or the HALT EXECUTION WHEN IDLE command, is also used to terminate a strong pullup or
programming pulse of semi-infinite or infinite duration.
CANCEL COMMAND
– This command is used to terminate the Communication command that is
currently being executed and place the 1-Wire bus in an idle state. Further Communication command
processing is stopped until a START EXECUTION command is received. The canceled Communication
command cannot be resumed. The DS2490 must be in a halted state before the CANCEL COMMAND
command can be processed, if not, the command will be ignored.