SH7619 Datasheet, PDF (570/836 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7619 Series

Section 17 Host Interface (HIF)
17.10 Interface When External Device Power is Cut Off
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 17.12 shows an image of high-impedance control of the HIF pins. Table 17.8 lists the
input/output control for the HIF pins.
HIFD15 to HIFD00
HIFCS
HIFRS
HIFWR
HIFRD
HIFMD
HIFINT
HIFDREQ
HIFRDY
HIFEBL
Figure 17.12 Image of High-Impedance Control of HIF Pins by HIFEBL Pin
Rev. 5.00 Mar. 15, 2007 Page 532 of 794
REJ09B0237-0500