Specifications

Built-in functions setPinPullup():
The setPinPullup() function does not apply a pull-up to GPIO_30 through GPIO_41. No
internal pull-ups are available on these pins, and it is not recommended that external pull-ups be
applied as they do not function well with the keepers that must be applied to those pins to allow them
to function as digital inputs or outputs rather than ADCs or VREFs. If your design requirements
mandate that an input have a pull-up or pull-down resistor, it would be best to use a different pin.
Built-in functions setPinSlew():
The setPinSlew() function configures the pin’s hysteresis rather than setting a slew rate.
Built-in functions setRadioRate():
The setRadioRate() function does not do anything on the MC13224. The only radio rate
available is the default rate of 250 Kbps, compatible with other 2.4 GHz-based SNAP nodes.
Built-in functions sleep():
There are four sleep() modes on the MC13224 module. Even-numbered sleep modes do not require
that an external 32 kHz crystal be connected, and are less accurate with their timing. (The internal
clock can be regulated on a node-by-node basis, if necessary, using NV Parameter 65.) Odd-numbered
sleep modes provide very accurate timing, but require the presence of the external crystal.
Sleep Mode Details
0, 1
• Fast recovery
• GPIO states are maintained during sleep
16
• Highest current usage
2, 3
• Fast recovery
• GPIO states are NOT maintained (though they are reset on waking)
Negative durations for sleep values are valid for these seven enumerations. The sleep durations listed
here represent the time the node spends sleeping, and do not include the node’s recovery time.
Ticks enumeration Sleep duration
-1 15.625 ms
-2 31.25 ms
-3 62.5 ms
-4 125 ms
-5 250 ms
-6 500 ms
-7 1000 ms
The first odd-mode sleep (using the external crystal) after a reboot of the node requires additional time
to enable the crystal.
16
Pins GPIO_22, GPIO_23, GPIO_24, and GPIO_25 will always shift to being outputs while the node is sleeping in all
sleep modes. Pins GPIO_26, GPIO_27, GPIO_28, and GPIO_29 will always shift to being inputs while the node is
sleeping in all sleep modes.
Page 182 of 202 SNAP Reference Manual Document Number 600-0007K