Cautions On Emulation - NEC mPD780973 Series Preliminary User's Manual

16.9 Cautions on Emulation

(1) LCD timer control register (LCDTM)
To perform debugging with an in-circuit emulator (IE-78K0-NS), the LCD timer control register (LCDTM) must
be set. LCDTM is a register used to set a probe board (IE-780974-NS-EM1).
LCDTM is a write-only register that controls supply of the LCD clock. Unless LCDTM is set, the LCD controller/
driver does not operate. Therefore, set bit 1 (TMC21) of LCDTM to 1 when using the LCD controller/driver.
Figure 16-12. LCD Timer Control Register (LCDTM) Format
Address: FF4AH After Reset: 00H W
Symbol 7
LCDTM 0
TMC21
0
1
Cautions 1. LCDTM is a special register that must be set when debugging is performed with an in-circuit
emulator. Even if this register is used, the operation of the µ PD780973 Subseries is not
affected. However, delete the instruction that manipulates this register from the program at
the final stage of debugging.
2. Bits 7 to 2, and bit 0 must be set to 0.
CHAPTER 16 LCD CONTROLLER/DRIVER
6 5
0 0
LCD controller/driver stop mode (supply of LCD clock is stopped)
LCD controller/driver operating mode (supply of LCD clock is enabled)
4 3 2
0 0 0
LCD Clock Supply Control
1 0
TMC21 0
203