W78LE365 datasheet(21/42 Pages) WINBOND

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W78LE365/W78L365A

Publication Release Date: January 10, 2007

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Revision A7

5.10

Software Reset

Set CHPCON = 0X83, timer and enter IDLE mode. CPU will reset and restart from APFLASH after

time out.

5.11

H/W Reboot Mode (Boot from LDROM)

By default, the W78L365A boots from APROM program after a power on reset. On some occasions,

user can force the W78L365A to boot from the LDROM program via following settings. The possible

situation that you need to enter H/W REBOOT mode when the APROM program can not run properly

and device can not jump back to LDROM to execute in-system programming function. Then you can

use this H/W REBOOT mode to force the W78L365A jumps to LDROM and executes in-system

programming procedure. When you design your system, you may reserve the pins P2.6, P2.7 to

switches or jumpers. For example in a CD-ROM system, you can connect the P2.6 and P2.7 to PLAY

and EJECT buttons on the panel. When the APROM program fails to execute the normal application

program. User can press both two buttons at the same time and then turn on the power of the

personal computer to force the W78L365A to enter the H/W REBOOT mode. After power on of

personal computer, you can release both buttons and finish the in-system programming procedure to

update the APROM code. In application system design, user must take care of the P2, P3, ALE, EA

and PSEN pin value at reset to prevent from accidentally activating the programming mode or H/W

REBOOT mode. It is necessary to add 10K resistor on these P2.6, P2.7 and P4.3 pins.

H/W Reboot MODE

P4.3

P2.7

P2.6

MODE

REBOOT

P2.7

P2.6

RST

30 mS

Hi-Z

The Reset Timing For Entering

F04KBOOT Mode

10 mS

Hi-Z

W78LE365 Datasheet(PDF) 21 Page - Winbond