User Manual

Apollo3 Blue Datasheet
DS-A3-0p9p1 Page 390 of 909 2019 Ambiq Micro, Inc.
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and PAD6RSEL fields should be set to select the desired pullup resistor size as shown in Table 563. If
external pullup resistors are used, PAD5PULL and PAD6PULL should be cleared.
11.5.1.2 IO Master 1 I
2
C Connection
I
2
C mode of IO Master 1 uses pad 8 as SCL and pad 9 as SDA. This mode is configured by setting the
PADnFNCSEL fields as shown in Table 567. The PAD8INPEN and PAD9INPEN bits must be set. If the
internal I
2
C pullup resistors are to be used, PAD8PULL and PAD9PULL should be set, and the PAD8RSEL
and PAD9RSEL fields should be set to select the desired pullup resistor size as shown in Table 563. If
external pullup resistors are used, PAD8PULL and PAD9PULL should be cleared.
11.5.1.3 IO Master 2 I
2
C Connection
I
2
C mode of IO Master 2 uses pad 27 as SCL and pad 25 as SDA. This mode is configured by setting the
PADnFNCSEL fields as shown in Table 568. The PAD27INPEN and PAD25INPEN bits must be set. If the
internal I
2
C pullup resistors are to be used, PAD27PULL and PAD25PULL should be set, and the
PAD27RSEL and PAD25RSEL fields should be set to select the desired pullup resistor size as shown in
Table 563. If external pullup resistors are used, PAD27PULL and PAD25PULL should be cleared.
11.5.1.4 IO Master 3 I
2
C Connection
I
2
C mode of IO Master 3 uses pad 42 as SCL and pad 43 as SDA. This mode is configured by setting the
PADnFNCSEL fields as shown in Table 569. The PAD42INPEN and PAD43INPEN bits must be set. If the
internal I
2
C pullup resistors are to be used, PAD42PULL and PAD43PULL should be set, and the
Table 566: IO
Master 0 I
2
C Configuration
Field Value
PAD5FNCSEL 0
PAD6FNCSEL 0
Table 567: IO Master 1 I
2
C Configuration
Field Value
PAD8FNCSEL 0
PAD9FNCSEL 0
Table 568: IO Master 2 I
2
C Configuration
Field Value
PAD27FNCSEL 4
PAD25FNCSEL 4