User System Interface; Signal Protection; User System Interface Circuits - Renesas H8 Series User Manual

7.2 User System Interface

All user system interface signals are directly connected to the MCU in the emulator with no buffering except for
those listed below which are connected to the MCU through control circuits:
• NMI
• /RES
• OSC1
• X1
• TEST
• V
CL
7.2.1

Signal Protection

All user system interface signals are protected from over- or under-voltage by use of diode arrays except for the
AVcc.
Pull-up resistors are connected to the port signals except for the analog port signals.
The Vcc pins (except for the AVcc pin) at the head of the user system interface cable are connected together.
The emulator monitors the voltage level of the Vcc pins and displays the power-supply status in the [Extended
Monitor] window.
If the user system interface cable is not connected to the user system, the Uvcc of the MCU is 5 V.
7.2.2

User System Interface Circuits

The interface circuit between the MCU in the emulator and the user system has a signal delay of about 8 ns due
to the user system interface cable and it includes pull-up resistors. Therefore, high-impedance signals will be
pulled up to the high level. When connecting the E6000 emulator to a user system, adjust the user system
hardware to compensate for propagation delays.
Default:
/RES and NMI: The NMI signal is input to the MCU through the emulator control circuit. The rising/falling
time of the signal must be 8 ns/V or less.
Figure 7.2 User System Interface Circuit for /RES and NMI
Figure 7.1 Default User System Interface Circuit
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