Renesas M34286T2-CPE, Руководство пользователя

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M34286T2-CPE User’s Manual 4. Hardware Specifications
R20UT0214EJ0200 Rev.2.00 Page 53 of 70
Sep 16, 2010
4.2 Differences between the Actual MCU and Emulator
Differences between the actual MCU and emulator are shown below. When debugging the MCU using this product, be
careful about the following precautions.
IMPORTANT
Note on Differences between the Actual MCU and Emulator:
•
Operations of the emulator differs from those of actual MCUs as listed below.
(1) Initial values of internal resource data of an MCU at power-on
With the emulator system, the ROM area at power-on is initialized to 000h (NOP instruction).
(2) Voltage drop detection circuit
Because the operating voltage of this product is fixed to 3V or 5V, it cannot evaluate any system
using a voltage drop detection circuit.
(3) Power-on reset
You can reset this emulator system by the reset command of the emulator debugger PD72M,
however, this emulator system cannot emulate operation at a power-on reset. Therefore, check the
operation at a power-on reset using an actual MCU.
(4)
Internal pull-down transistor control
Because an emulation circuit exists among ports D0 to D7, G0 to G3 and E0, this emulator system
cannot control pull-down transistors by the control resistor of an MCU. To use the internal
pull-down transistor, set SW1 to SW11 to the "ON" side. By the settings, each port is pulled down
with a 150 k
Ω
pull-down resistor.
(5)
Unconnected pins
Pins below are not connected to the user system
- XIN, XOUT
Notes on Operating Clock:
•
The clock generated on the OSC board only is usable as the operating clock, and the clocks listed below
cannot be used.
(1) External input clocks on the user system.
•
The clock input to the MCU is supplied from the oscillator circuit board OSC-2 in the emulator, and
cannot be supplied from an oscillator circuit in the user system.
If the system clock frequency needs to be changed, alter the circuit on the oscillator circuit board OCS-2
before use. For details, refer to Section 2.3.2, “Selecting Clock Supply” (page 24).