Datasheet
71M6543F/71M6543G Data Sheet   
76    v2   
Transitions from both LCD and SLP mode to BRN mode can be initiated by the following events: 
•  Wake-up timer timeout. 
•  Pushbutton (PB) is activated. 
•  A rising edge on SEGDIO4, or a high logic level on SEGDIO52 or SEGDIO55. 
•  Activity on the RX or OPT_RX pins. 
The MPU has access to a variety of registers that signal the event that caused the wake up. See 3.4 
Wake-Up Behavior for details. 
Table 61 shows the circuit functions available in each operating mode. 
Table 61: Available Circuit Functions 
Circuit Function 
System Power 
Battery Power 
MSN (Mission Mode) 
BRN (Brownout Mode) 
LCD  SLEEP 
PLL_FAST=1 
PLL_FAST=0 
PLL_FAST=1 
PLL_FAST=0 
CE (Computation Engine) 
Yes 
Yes 
--
1
-- 
-- 
-- 
FIR 
Yes 
Yes 
-- 
-- 
-- 
-- 
ADC, VREF 
Yes 
Yes 
-- 
-- 
-- 
-- 
PLL 
Yes 
Yes 
Yes 
Yes 
Boost
2
-- 
Battery Measurement 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
Temperature sensor 
Yes 
Yes 
Yes 
Yes 
Yes 
Yes 
Max MPU clock rate 
4.92MHz  
(from PLL) 
1.57MHz  
(from PLL) 
4.92MHz  
(from PLL) 
1.57MHz  
(from PLL) 
--  -- 
MPU_DIV clk. divider 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
ICE 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
DIO Pins 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
Watchdog Timer 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
LCD 
Yes 
Yes 
Yes 
Yes 
Yes 
-- 
LCD Boost 
Yes 
Yes 
Yes 
Yes 
Yes 
EEPROM Interface (2-wire) 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
EEPROM Interface (3-wire) 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
UART (full speed) 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
Optical TX modulation 
38.4kHz 
38.9kHz 
38.4kHz 
38.9kHz 
-- 
-- 
Flash Read 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
Flash Page Erase 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
Flash Write 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
RAM Read and Write 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
Wakeup Timer 
Yes 
Yes 
Yes 
Yes 
Yes 
Yes 
OSC and RTC 
Yes 
Yes 
Yes 
Yes 
Yes 
Yes 
DRAM data preservation 
Yes 
Yes 
Yes 
Yes 
-- 
-- 
NV RAM data preservation 
Yes 
Yes 
Yes 
Yes 
Yes 
Yes 
Notes: 
1.  “--“ indicates that the corresponding circuit is not active 
2.  “Boost” implies that the LCD boost circuit is active (i.e., LCD_VMODE[1:0] = 10 (I/O RAM 0x2401[7:6])). The LCD boost 
circuit requires a clock from the PLL to function. Thus, the PLL is automatically kept active if LCD boost is active while in 
LCD mode, otherwise the PLL is de-activated. 










