NEC PD703114 User Manual page 608

15.5 Pin Connection
When performing on-board writing, install a connector on the target system to connect to the dedicated flash
programmer. Also, install a function on-board to switch from the normal operation mode (single-chip mode or
ROMless mode) to the flash memory programming mode.
In the flash memory programming mode, all the pins not used for flash memory programming become the same
status as they were immediately after reset in single-chip mode. Therefore, all the ports become output high-
impedance status, so that pin connection is required when the external device does not acknowledge the output high-
impedance status.
15.5.1 MODE1/V pin
PP
In the normal operation mode, 0 V is input to the MODE1/V
writing voltage is supplied to the MODE1/V
MODE1/V pin.
PP
15.5.2 Serial interface pin
The following shows the pins used by each serial interface.
When connecting a dedicated flash programmer to a serial interface pin that is connected to other devices on-
board, care should be taken to avoid the conflict of signals and the malfunction of other devices, etc.
(1) Conflict of signals
When connecting a dedicated flash programmer (output) to a serial interface pin (input) which is connected to
another device (output), a conflict of signals occurs. To avoid the conflict of signals, isolate the connection to
the other device or set the other device to the output high-impedance status.
608
CHAPTER 15 FLASH MEMORY (
pin.
PP
Figure 15-5. Connection Example of MODE1/V
V850E/IA2
Dedicated flash programmer connection pin
MODE1/V
PP
Table 15-3. Pins Used by Each Serial Interface
Serial Interface
CSI0
CSI0 + HS
UART0
User's Manual U15195EJ5V0UD
µ
PD70F3114)
pin. In the flash memory programming mode, 7.8 V
PP
The following shows an example of the connection of the
PP
Pull-down resistor (R = 5 to 50 kΩ)
VPP
Pins Used
SO0, SI0, SCK0
SO0, SI0, SCK0, PDH0
TXD0, RXD0
Pin