HD6417618 RENESAS [Renesas Technology Corp], HD6417618 Datasheet - Page 451

• Manufacturer Part Number: HD6417618
• Description: 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7618 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

15.9
When the power supply of an external device interfacing with the HIF is cut off, intermediate
levels may be applied to the HIF input pins or the HIF output pins may drive an external device
not powered, thus causing the device to be damaged. The HIFEBL pin is provided to prevent this
from happening. The system power monitor block controls the HIFEBL pin in synchronization
with the cutoff of the external device power so that all HIF pins can be set to the high-impedance
state. Figure 15.12 shows an image of high-impedance control of the HIF pins. Tables 15.6 and
15.7 list the input/output control for the HIF pins.
Figure 15.12 Image of High-Impedance Control of HIF Pins by HIFEBL Pin
Interface When External Device Power is Cut Off
HIFD15 to HIFD00
HIFDREQ
HIFRDY
HIFEBL
HIFWR
HIFMD
HIFINT
HIFRD
HIFCS
HIFRS
Rev. 6.00 Jun. 12, 2007 Page 419 of 610
Section 15 Host Interface (HIF)
REJ09B0131-0600