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1.5 Recommended Circuit between the H-UDI Port Connector and the
MPU
1.5.1 Recommended Circuit (36-Pin Type)
Figure 1.3 shows a recommended circuit for connection between the H-UDI and AUD port
connectors (36 pins) and the MPU when the emulator is in use.
Notes: 1. Do not connect anything to the N.C. pins of the H-UDI port connector.
2. The /ASEMD0 pin must be 0 when the emulator is connected and 1 when the
emulator is not connected, respectively.
(1) When the emulator is used: /ASEMD0 = 0
(2) When the emulator is not used: /ASEMD0 = 1
Figure 1.3 shows an example of a circuit that allow the /ASEMD0 pin to be GND (0)
whenever the emulator is connected by using the user system interface cable.
When the /ASEMD0 pin is changed by switches, etc., ground pin 22. Do not connect
this pin to the /ASEMD0 pin.
3. When a network resistance is used for pull-up, it may be affected by a noise. Separate
TCK from other resistances.
4. The /CA signal in the user system is input to the /CA pin of the MPU. Connect this
signal to the H-UDI port connector as the output from the user system.
5. When the emulator is used, the /CA pin must be pulled up by a resistance of several
kilo-ohms whether the U-standby function is used or not.
6. The /TRST pin must be at the low level for a certain period when the power is
supplied whether the H-UDI is used or not. Reduce the power supplied to the /TRST
pin by pulling the pin up by a resistance of several kilo-ohms and setting HIZB8 = 0
in the HIZCRB register after a reset.
7. The pattern between the H-UDI port connector and the MPU must be as short as
possible. Do not connect the signal lines to other components on the board.
8. Since the H-UDI and the AUD of the MPU operate with the VccQH, supply only the
VccQH to the UVCC pin. Make the emulator’s switch settings so that the VccQH will
be supplied (SW2 = 1 and SW3 = 1) (as shown in figure 1.3).
9. The resistance values shown in the figure are recommended.
10. For the pin processing in cases where the emulator is not used, refer to the hardware
manual of the related MPU.
11. Either 3.0 V or 1.8 V can be selected as VccQ for the /CA pin or the /RESETP pin due
to the MPU specifications. These pins must be pulled up by the voltage level of VccQ.
In addition, when VccQ is selected as 1.8 V, VccQ is boosted because the lower limit
of the emulator’s UVCC or VccQH voltage is 2.5 V. However, it does not affect
MPU’s operation.