NEC switch - Manual (Page 32)

CHAPTER 2 PIN FUNCTIONS
User’s Manual U12978EJ3V0UD
32
2.2.12 V
PP
( µµµµPD78F9801 only)
A high voltage should be applied to this pin when the flash memory programming mode is set and when the
program is written or verified.
Handle this pin in either of the following ways.
• Independently connect a 10 kΩ pull-down resistor.
• Switch this pin to be directly connected to the dedicated flash programmer in programming mode or to V
SS0 in
normal operation mode using a jumper on the board.
2.2.13 IC (mask ROM version only)
The IC (Internally Connected) pin is used to set the µPD789800 Subseries in the test mode before shipment. In
the normal operation mode, directly connect this pin to the V
SS0
pin with as short a wiring length as possible.
If a potential difference is generated between the IC pin and V
SS0
pin due to a long wiring length between the IC
pin and V SS0 pin or an external noise superimposed on the IC pin, a user program may not run correctly.
• Directly connect the IC pin to the V
SS0 pin.
V SS0 IC
Keep short