W78E516DDG Datasheet, PDF (65/90 Pages) Nuvotem Talema – 8-BIT MICROCONTROLLER

W78E516D/W78E058D Data Sheet
17 F04KBOOT MODE (BOOT FROM 4K BYTES OF LDROM )
The W78E516D/W78E058D boots from APROM program memory(64K/32K bytes) by default at power
on reset or reset-pin reset. On some occasions, user can force the W78E516D/W78E058D booting
from the LDROM program memory (4K bytes) at power on reset or external reset. The settings for this
special mode as follow.
F04KBOOT MODE
P4.3
X
L
P2.7
L
X
P2.6
L
X
Mode
FO4KBOOT
FO4KBOOT
The Reset Timing For Entering
F04KBOOT Mode
P2.7
Hi-Z
P2.6
Hi-Z
RST
300ms
10ms
T h e R e se t T im in g F o r
E n te rin g F 0 4 K B O O T M o d e
P 4 .3
RST
300 m s
10 m s
H i-Z
NOTE1: The possible situation that you need to enter F04KBOOT mode is when the APROM program
can not run normally and W78E516D/W78E058D can not jump to LDROM to execute on chip pro-
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Publication Release Date: Feb 15, 2011
Revision A09