Specifications

NOTE – The ZICM2410P2, which includes a power amplifier, requires that you have P3.2 (pin 18)

and P3.3 (pin 19) pulled high (CEL recommends a 10 KΩ pull-up resistor between VCC and the pins)

in order to prevent internal interrupts from waking the module prematurely when sleep modes 1 and 2

are used.

For more information on the sleep modes of the ZIC2410, refer to the manufacturers data sheets.

In each mode, one tick is one second. The maximum sleep duration for timed sleep on the ZIC2410 is

256 seconds. Time values larger than 256 will be reduced by modulo 256 (e.g., values of 258 or 514

would both result in 2-second sleeps). No “negative” sleep durations are supported.

NOTE – The ZIC2410 data sheets refer to 4 “power modes,” where 0 is awake, and “power modes” 1-

3 correspond to SNAPpy sleep modes 0-2.

Performance Metrics

Here are the results of some performance measurements, which may help you gauge if SNAPpy can

address your application’s timing requirements.

These results are for the California Eastern Labs ZIC2410.

Time to awaken from sleep (mode 0):

< 200 microseconds

Time to startup from power-on:

< 60 milliseconds

Maximum rate a SNAPpy script can toggle a GPIO pin:

528.5 Hz

Keep in mind that as a general rule, SNAPpy scripts should not be looping, the above rate is only

attainable if the node is doing nothing else (for example, no radio or serial port communication).

Maximum rate for readAdc() calls:

maximum 696 samples/second

NOTE! – This measurement was taken using a script that did not actually do anything with the data.

You will also have to take into consideration any numeric processing required (data thresholding, etc.),

as well as the need to actually store the data someplace.

C Byte Transfer Time

The actual I

C transfers are done using “bit banging” in software. This was measured using a logic

analyzer at 710 µs per byte.

SNAP Reference Manual Document Number 600-0007K Page 149 of 202