Section 2 User System Interface; Signal Protection; User System Interface Circuits - Renesas SH7040 Series Supplementary Information

All user system interface signals are directly connected to the MCU in the E6000 with no buffering
except for those listed below which are connected to the MCU through control circuits:
• NMI
• RES
• MD3, MD2, MD1, MD0
• EXTAL
• WDTOVF
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 E6000 monitors this and determines whether the user system is
connected.
2.2

User System Interface Circuits

The interface circuit between the MCU in the E6000 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 to a user
system, adjust the user system hardware to compensate for propagation delays.
The following diagrams show the interface signal circuits.
Default:

Section 2 User System Interface

Figure 2.1 Default User System Interface Circuit
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