Reset and Boot Entrance
There could be five conditions will cause the device to be reset.
Power-Up
RST pin press
Watch Dog Timer overflows
Reset from Low-Voltage-Detector
Software invokes
The following procedure describes how does this device select the boot entrance.
Power-Up
If ( (HWBS==0) or (HWBS2==0) ) then
SWBS
= 1
else
SWBS
keeps unchanged
end
If (SWBS==1) {
Boot from ISP code
else
Boot from AP code
RST-pin press
(HWBS2==0) then
SWBS
= 1
else
SWBS
keeps unchanged
end
If (SWBS==1) {
Boot from ISP code
else
Boot from AP code
d
If
The RST pin is used to reset this device. It is connected into the device to a Schmitt
Trigger buffer to get excellent noise immunity.
Any positive pulse from RST pin must be kept at least 10us plus 36 oscillation cycles, or
the device cannot be reset.
WDT overflow, LVD reset,
and
Software reset
SWBS
keeps unchanged
If (SWBS==1) {
Boot from ISP code
else
Boot from AP code
end
MEGAWIN
MPC82x54A Data Sheet
59
MEGAWIN [ MEGAWIN TECHNOLOGY CO., LTD ]
