04.03.2013 Views

RL78/D1A User's Manual: Hardware - Renesas

RL78/D1A User's Manual: Hardware - Renesas

RL78/D1A User's Manual: Hardware - Renesas

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Under development<br />

Preliminary document<br />

Specifications in this document are tentative and subject to change.<br />

<strong>RL78</strong>/<strong>D1A</strong> CHAPTER 25 SAFETY FUNCTIONS<br />

(2) Specific register manipulation protection register (GUARD)<br />

This register is used to control the guard function.<br />

GDRTC and GDPLL bits are used in SFR guard function.<br />

The GUARD register can be set by an 8-bit memory manipulation instruction.<br />

Reset signal generation clears this register to 00H.<br />

Figure 25-10. Format of Specific Register Manipulation Protection Register (GUARD)<br />

Address: F00FCH After reset: 00H R/W<br />

Symbol 7 6 5 4 3 2 1 0<br />

GUARD 0 0 0 0 0 0 GDRTC GDPLL<br />

GDRTC Protection against RTC clock selection register (RTCCL)<br />

0 RTCCL register can be accessed.<br />

1 Disables RTCCL register (GUARD is effective).<br />

GDPLL Protection against manipulation of PLL control register (PLLCTL)<br />

0 Enables manipulation of PLLCTL register.<br />

1 Disables manipulation of PLLCTL register (GUARD is effective).<br />

R01UH0317EJ0004 Rev. 0.04 1143<br />

Feb. 22, 2013

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!