SLAZ523AA August   2014  – August 2021 MSP430FR5989 , MSP430FR5989-EP

 

  1.   1
  2.   2
  3.   3
  4.   4
  5.   5
    1.     6
    2.     7
      1.      8
      2.      9
    3.     10
  6.   11
    1.     12
    2.     13
    3.     14
    4.     15
    5.     16
    6.     17
    7.     18
    8.     19
    9.     20
    10.     21
    11.     22
    12.     23
    13.     24
    14.     25
    15.     26
    16.     27
    17.     28
    18.     29
    19.     30
    20.     31
    21.     32
    22.     33
    23.     34
    24.     35
    25.     36
    26.     37
    27.     38
    28.     39
    29.     40
    30.     41
    31.     42
    32.     43
    33.     44
    34.     45
    35.     46
    36.     47
    37.     48
    38.     49
    39.     50
    40.     51
    41.     52
    42.     53
    43.     54
    44.     55
    45.     56
    46.     57
    47.     58
  7.   59

6.33 PMM27

PMM Module

Category

Functional

Function

Device may reset when waking up from LPM2 or LPM3

Description

When the device is in LPM2/LPM3 and the eUSCI UART module is enabled and waiting to receive a byte, an unintentional device reset (BOR) may be triggered if the following two conditions are met:

1) There are exactly five other peripherals (excluding the eUSCI UART) that are both active AND requesting ACLK for example Timer_A or RTC

AND

2) Interrupts from other peripherals occur within a 1us time window of the eUSCI UART detecting the start bit of the first received byte

Workaround

Do not use exactly five active peripherals requesting ACLK, when the eUSCI UART is enabled in LPM2/LPM3. Instead use less than OR greater than five active peripherals  to prevent a BOR from occurring.