UPD78F1502AGK-GAK-AX Datasheet, PDF (854/1031 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcontrollers

78K0R/Lx3
CHAPTER 27 FLASH MEMORY
27.4.2 TOOL0 pin
In the flash memory programming mode, connect this pin directly to the dedicated flash memory programmer or pull it
up by connecting it to EVDD via an external resistor.
When on-chip debugging is enabled in the normal operation mode, pull this pin up by connecting it to VDD via an
external resistor, and be sure to keep inputting the VDD level to the TOOL0 pin before reset is released (pulling down this
pin is prohibited).
Remark The SAU and IICA pins are not used for communication between the 78K0R/Lx3 microcontrollers and
dedicated flash memory programmer, because single-line UART is used.
27.4.3 RESET pin
Signal conflict will occur if the reset signal of the dedicated flash memory programmer is connected to the RESET pin
that is connected to the reset signal generator on the board. To prevent this conflict, isolate the connection with the reset
signal generator.
The flash memory will not be correctly programmed if the reset signal is input from the user system while the flash
memory programming mode is set . Do not input any signal other than the reset signal of the dedicated flash memory
programmer.
Figure 27-5. Signal Conflict (RESET Pin)
78K0R/Lx3
microcontrollers
Input pin
Signal conflict
Dedicated flash memory programmer
connection pin
Another device
Output pin
In the flash memory programming mode, a signal output by another device
will conflict with the signal output by the dedicated flash memory
programmer. Therefore, isolate the signal of another device.
27.4.4 Port pins
When the flash memory programming mode is set, all the pins not used for flash memory programming enter the same
status as that immediately after reset. If external devices connected to the ports do not recognize the port status
immediately after reset, the port pin must be connected to VDD or VSS via a resistor.
27.4.5 REGC pin
Connect the REGC pin to GND via a capacitor (0.47 to 1 μF) in the same manner as during normal operation.
Also, use a capacitor with good characteristics, since it is used to stabilize internal voltage.
27.4.6 X1 and X2 pins
Connect X1 and X2 in the same status as in the normal operation mode.
Remark In the flash memory programming mode, the internal high-speed oscillation clock (fIH) is used.
R01UH0004EJ0501 Rev.5.01
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Jun 20, 2011