USBB17RX78K4-XXX NEC Electronics, USBB17RX78K4-XXX Datasheet - Page 76

• Manufacturer Part Number: USBB17RX78K4-XXX
• Description: 78K/4 series realtime OS
• Manufacturer: NEC Electronics

internal ROM or external memory of the 78K/IV series is expected.
sure to set the address of the user’s initialization routine. Make sure that the user initial routine performs necessary
processing such as initialization of the peripheral hardware. After this, read out the location address of the kernel
from the initialization information table created by the configurator, and branch to the reset routine for system
initialization. At this time, set the top address of the initialization information table to the TDE register.
initialization information table. After initialization, control is passed to the RX78K/IV dispatcher. The dispatcher
selects a task from a ready queue initialized by the reset routine and places the task in the RUN state. The task
selected at this time is called an initial task.
A system running RX78K/IV is initialized when the system initialization reset routine stored with RX78K/IV in the
After resetting the device, the system is branched out to the address which is set in address 0000H. Therefore, be
Fig. 5-1 shows an example program to branch to the reset routine for system initialization.
The reset routine for system initialization initializes the reserved area and object in accordance with the
;
;
VCTTB10
VCTTBL1
RESRTN
RES_RTN:
;
Fig. 5-1 Reset Routine Branch Program for System Initialization (Large model)
NAME
EXTRN
CSEG
DW
CSEG
DW
CSEG
LOCATION 0FH
(Initialization of RAM, initialization of peripheral hardware, etc.)
MOVG
MOVW
BR
END
AT 0000H
AT 0018H
RES_PROG
SYS_INF,
RES_RTN
?TMDSP
TDE, #SYS_INF
AX, [TDE]
AX
CHAPTER 5
RX78K/IV RESET OPERATION
; initialization information table
; sets vector address at reset
; sets vector address for timer processing
; sets top address of the initialization
; sets kernel location address to AXreg.
; branches to the reset routine for system
information table to TDEreg.
initialization of RX78K/IV
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