User Manual

Apollo3 Blue Datasheet
DS-A3-0p9p1 Page 572 of 909 2019 Ambiq Micro, Inc.
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13.20Pad Connections from the Timer/Counter
In order to provide flexibility in connecting timers to external devices, a secondary multiplexing mechanism
is provided for the timer outputs. There are 32 pads which can be configured for either inputs to or outputs
from the Timer/Counter module. Each of these pads can be driven by one of four outputs selected by the
REG_CTIMER_OUTCFG0/1/2/3 registers, as shown in Table 818. The ctimer_out column specifies the bit
in REG_GPIO_CTENCFG (EN0-EN31) which enables the corresponding pad CT0-31 output. The Output
Selection columns define the output choices for each output based on the CFG fields in OUTCFGx, where
CFG=0 forces the output to 0, CFG=1 forces the output to 1 and CFG=2 through 7 produce the choices in
the table. The shaded cells indicate selections which correspond to the Timer/Counter connections in
previous Apollo3 devices..