Differences In Port Functions; Differences In Sfr-Registers; Target Interface Circuit - NEC IE-78K0-NS-P04 Preliminary User's Manual

4.2 Differences in Port Functions

(1) Port 3.6, Port 4, Port 6.0 to 6.3 and Port 9.2 of the device are normal CMOS inputs with no hysteresis.
The emulator has pins with hysteresis.
(2) The LCD-segment signals S0-S27 are input/output ports of type 17A/17B at the device. The emulator
drives these signals by an analog switch.
(3) The power fail detection is implemented as analogue comparator instead of a digital comparator on
the device.

4.3 Differences in SFR-Registers

Caution: 1. The emulator has a register to emulate the powerfail detection which is not existing
at the real chip. The name of the register is DAM0 (SFR-Adr: 0xFF9C). This register
has to be set to the value 0x01 by the user program.
2. The emulator has a register for the emulation of the LCD-function. The name of the
register is LCDTM (SFR-Adr: 0xFF4A). This register has to be set to the value 0x02
by the user program.

4.4 Target Interface Circuit

The purpose of the target interface circuit is to have the same operations as the target device performed
in the IE-78K0-NS-A. It comprises the emulation device and various dates (CMOS, TTL and othes ICs).
When debugging is performed with the target system connected
78K0-NS-A target interface circuit performes emulation as though the actual target device were
operating in the target system.
The target device has a CMOS LSI configuration. The target interface circuit emulator device also has
a CMOS LSI configuration, and is virtually identical to the target device in terms of DC characteristics
and AC characteristics (when operating on V
However, where emulation device signal input/output is performed via gates in the target interface
circuit, DC and AC characteristics differ from those of the target device.
In particular, regarding AC characteristics, there is a date delay time (which differs from date to date)
each time a gate is passed through.
The above points must be taken into consideration when designing the target system.
Caution: When the IE-78K0-NS-A and IE-78K0-NS-P04 and IE-780828-NS-EM4 are connected to
the target system, 4.0 to 5.5 V must be supplied as the target system power supply
(V ).
DD
IE-78K0-NS-P04, IE-780828-NS-EM4
= 4.0 to 5.5 V).
DD
to the IE-78K0-NS-A, the IE-
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