UPD72042BGT NEC [NEC], UPD72042BGT Datasheet - Page 73

• Manufacturer Part Number: UPD72042BGT
• Description: LSI DEVICE FOR Inter Equipment Bus (IEBus) PROTOCOL CONTROL
• Manufacturer: NEC [NEC]

6.4.3 Command Processing Routine
transmission/reception buffers, control communication, and set optional functions.
and 6.4.5.
6.4.4 Master Communication Processing Routine
This routine is executed when CORQ has been set by the application processing routine.
The command processing routine sets a command code, in the CMR register, to set the lock state, control
The commands for master communication and slave data transmission request are described in Sections 6.4.4
Fig. 6-5 shows the flow of the command processing routine.
This routine is executed when MCRQ has been set by the application processing routine.
The master communication processing routine consists of the following three processing routines:
• Master transmission processing routine 1
• Master transmission processing routine 2
• Master reception processing routine
This routine is used to transmit data, as the master unit, starting from the first data in TBF.
This routine is used to start master transmission from the point at which the previous master transmission was
suspended.
This routine is used to receive data, as the master unit, from a slave unit.
Fig. 6-5 Command Processing Routine
1
CMR
Data Sheet S13990EJ3V0DS
Read FLG
Command code
CEX?
Start
End
0
;
Waiting for termination
of previous command?
PD72042B
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