71M6521BE-DB Maxim Integrated Products, 71M6521BE-DB Datasheet - Page 67

• Manufacturer Part Number: 71M6521BE-DB
• Description: Power Management Modules & Development Tools 71M6521BE DEMO BOARD M6521BE DEMO BOARD
• Manufacturer: Maxim Integrated Products

Specifications of 71M6521BE-DB

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

71M652X Software User’s Guide
After a reset or power up, the processor must first decide what mode it is in and then take the appropriate action. It is
useful to concentrate all activities related to power modes and reset into one centralized module. The Demo Code
revision 4.7a does the switching of modes in the main() routine, based on decisions made in batmodes_20.c. Figure
5-21 shows the actions taken by the Demo Code and chip hardware after entering the main() routine. The code uses
the following inputs and flags to determine which mode to enter:
Revision 1.7
5.5
•
•
•
•
N
MANAGING MISSION AND BATTERY MODES
Battery mode enable jumper (see the DBUM for a detailed description of this input)
PLL_OK flag
RESET input
PB input
Clear Overflow flag
Restart Hardwrare
Set Status register
Invoke Soft Reset
has overflowed ?
Check if HWDT
Mission mode
Y
Is PLL ok ?
Is battery
enabled?
Y
mode
WDT
Y
main
N
N
Start here:
1. On power up
2. On HWDT Overflow
3. If PB pressed
4. On wake up from LCD or Sleep Modes
5. If Reset Button Pressed
6. Soft Reset function invoked.
© Copyright 2005-2007 TERIDIAN Semiconductor Corporation
On power up, will remain in
this loop till PLL ok flag is
set and "Brownout
interrupt" occurs which
invokes a "Soft Reset"
Run Main Loop
Initialise Main
Sleep mode
Already in
Brownout
mode?
Y
Figure 5-21: Power-Up Sequence
N
TERIDIAN Proprietary
Brownout Mode
Pressed?
Is Reset
Button
Y
N
Y
LCD mode
Pressed?
Is Push
Button
Checked by Hardware
N
Sleep mode
Present ?
Is V3P3
Sys
N
67 of 138
Y