Chapter 5 Cautions - NEC IE-789860-NS-EM1 User Manual

This chapter describes differences between the target device specifications and the IE system specifications. The
emulation circuit of the IE system realizes emulation via a configuration of emulation CPU, TTL, CMOS-IC, and other
components. Therefore, the target device specifications are different from the IE system specifications.
(1) The RC oscillator cannot be emulated in the IE-789860-NS-EM1. For the oscillator, only the functions
described in 3.4 Clock Settings can be emulated.
(2) When emulating the detection voltage of the low-voltage detection circuit and power-on-clear circuit in the IE-
789860-NS-EM1, the detection voltage must be finally checked with EEPROM products because of the effect
of power supply fluctuations and noise.
(3) If a program that illegally accesses EEPROM is executed in the IE-789860-NS-EM1, the error message
"Unspecified illegal" is displayed and a break occurs. The illegal access conditions for EEPROM are shown
in Table 5-1.
<1> If a write instruction is executed to EEPROM when EWC = 0
<2> If a write instruction is executed to EEPROM while the clock selected by EEPROM is stopped
<3> If a write instruction is executed to EEPROM while EEPROM is being written
<4> If read instruction is executed from EEPROM while EEPROM is being written
<5> If instruction fetch is executed from EEPROM while EEPROM is being written
<6> If EWC = 0 is set while EEPROM is being written
<7> If the main clock is stopped while EEPROM is being written
<8> If the count clock selection of the write time setting timer is changed and executed while EEPROM is being written
<9> If RESET is input while EEPROM is being written
(4) The IE-789860-NS-EM1 includes a "POC switching circuit" that controls the power-on-clear (POC) circuit
functions by software. Perform the ON/OFF settings using an SFR.
(5) The oscillation stabilization wait time after the release of STOP mode by RESET or the release of reset via
the POC circuit is fixed to "2
described in 3.5 Mask Option Settings can be emulated.
CHAPTER 5
Table 5-1. Illegal Access Conditions for EEPROM
7
/f " in the IE-789860-NS-EM1.
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User's Manual U16499EJ1V0UM
CAUTIONS
For the mask options, only the functions
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