CHAPTER 2 PIN FUNCTIONS
2.2.16 IC0 (mask ROM version only)
The IC0 (Internally Connected) pin is used to set the µPD789188 to test mode before shipment. In normal
operation mode, directly connect this pin to the VSS pin with as short a wiring length as possible.
If a potential difference is generated between the IC0 pin and VSS pin due to a long wiring length between the IC0
pin and VSS pin or an external noise superimposed on the IC0 pin, a user program may not run correctly.
• Directly connect the IC0 pin to the VSS pin.
VSS0,
VSS1 IC0
Keep short
User’s Manual 2nd edition
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