SPRZ426F November   2014  – September 2024 DRA710 , DRA712 , DRA714 , DRA716 , DRA718 , DRA722 , DRA724 , DRA725 , DRA726

 

  1.   1
  2. 1Introduction
    1.     Related Documentation
    2.     Trademarks
    3.     Modules Impacted
  3. 2Silicon Advisories
    1.     Revisions SR 2.1, 2.0, 1.0 - Advisories List
    2.     i202
    3.     i378
    4.     i631
    5.     i694
    6.     i698
    7.     i699
    8.     i709
    9.     i727
    10.     i729
    11.     i734
    12.     i767
    13.     i782
    14.     i783
    15.     i802
    16.     i803
    17.     i807
    18.     i808
    19.     i809
    20.     i810
    21.     i813
    22.     i814
    23.     i815
    24.     i818
    25.     i819
    26.     i820
    27.     i824
    28.     i826
    29.     i829
    30.     i834
    31.     i849
    32.     i856
    33.     i862
    34.     i863
    35.     i867
    36.     i868
    37.     i869
    38.     i870
    39.     i871
    40.     i872
    41.     i874
    42.     i875
    43.     i878
    44.     i879
    45.     i880
    46.     i881
    47.     i882
    48.     i883
    49.     i887
    50.     i889
    51.     i890
    52.     i893
    53.     i895
    54.     i896
    55.     i897
    56.     i898
    57.     i899
    58.     i900
    59.     i903
    60.     i904
    61.     i906
    62.     i913
    63.     i916
    64.     i927
    65.     i928
    66.     i929
    67.     i930
    68.     i932
    69.     i933
    70.     i940
    71.     i2446
  4. 3Silicon Limitations
    1.     Revisions SR 2.1, 2.0, 1.0 - Limitations List
    2.     i596
    3.     i641
    4.     i833
    5.     i838
    6.     i844
    7.     i845
    8.     i848
    9.     i876
    10.     i877
    11.     i892
    12.     i909
    13.     i917
  5. 4Silicon Cautions
    1.     Revisions SR 2.1, 2.0, 1.0 - Cautions List
    2.     i781
    3. 4.1 95
    4.     i827
    5.     i832
    6.     i836
    7.     i839
    8.     i864
    9.     i885
    10.     i886
    11.     i912
    12.     i918
    13.     i920
    14.     i926
    15.     i931
    16.     i934
    17. 4.2 109
  6. 5Revision History

i833

I2C Module in Multislave Mode Potentially Acknowledges Wrong Address

CRITICALITY

Low

DESCRIPTION

When the I2C module is in multislave mode with up to four 10-bit own addresses it may acknowledge the wrong address. According to the I2C protocol, a 10-bit address is sent via 2 bytes. The first byte is formatted as 11110XX R/W where XX are the 2 MSB of the address. The second byte contains the remaining 8 bits of the device address.

When the first byte received contains 2 MSB that matches the 2 MSB of the one of the modules four own addresses, an ACK is correctly sent by the module. However, if the second byte received matches the remaining 8 bits of one of the modules other own addresses, an ACK is sent incorrectly by that module. In turn, the incorrect module then enters an internal state where starts reading data sent on the bus not intended for it.

The module should only send a second ACK if the entire 10-bit address matches one of its four own addresses. However, the module incorrectly ACKs any address that matches the first 2 bits of one slave address and the last eight bits of another slave address.

WORKAROUND

The issue can be avoided by ensuring that the 2 most significant bits are identical for all multislave addresses in 10-bit addressing mode.

REVISIONS IMPACTED

DRA72x SR 2.0, 1.0
DRA71x SR 2.1, 2.0

DRA79x: 2.1, 2.0

TDA2Ex (23mm): 2.0, 1.0

TDA2Ex (17mm): 2.1, 2.0

AM571x: 2.1, 2.0, 1.0

AM570x: 2.1, 2.0

DRA72x: 2.0, 1.0

DRA71x: 2.1, 2.0