Cautions On Debugging - NEC QB-MINI2 User Manual

CHAPTER 4

4.2.7 Cautions on debugging

This section describes cautions on performing on-chip debugging for a 78K0 microcontroller.
Be sure to read the following to use MINICUBE2 properly.
(1) Handling of device that was used for debugging
Do not mount a device that was used for debugging on a mass-produced product, because the flash memory
was rewritten during debugging and the number of rewrites of the flash memory cannot be guaranteed.
(2) Overwriting flash memory during on-chip debugging
If the following operations are performed during on-chip debugging, the flash memory in the device is
overwritten.
<1> Downloading a program
<2> Manipulation in Memory Fill dialog box
<3> Manipulation in Memory Copy dialog box
<4> Manipulation to change memory in Memory window
<5> Online assembly in Assemble window
<6> Settings when using software breaks
<7> Program execution or software reset operation, while " Permit " has been selected for the Target Power Off
setting in the Configuration dialog box
<8> Operation that uses pseudo real-time RAM monitor function
It takes time from completion of flash memory programming until the control is passed to GUI.
(3) Software break (1)
During program running, do not rewrite the data at the address where a software break is set. This includes
self programming and rewriting to RAM. If performed, the instruction placed at the address may be invalid.
(4) Boot swapping during self programming
The boot swapping function cannot be emulated. This is because boot swapping moves the memory spaces
used for debugging, and thus the debug communication can no longer be performed.
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HOW TO USE MINICUBE2 WITH 78K0 MICROCONTROLLER
User's Manual U18371EJ1V0UM