Specifications
Synapse RF200
SNAP Engines based on the ATmega128RFA1 are available. All the details appropriate for the chip-
based SNAP Modules (see the previous section) apply to the SNAP Engine, with the following
additions and exceptions. Pin numbers below refer to the pin on the SNAP Engine footprint. To
reference the pins in your code, use the SNAPpy IO number from the table below. Note that the SPI
and I
2
C locations are different on the RF200 than they are on the ATmega128RFA1.
RF200 SNAP Engines should not be used on the Synapse SN111 End Device board. The power-up
state of the pins conflicts with the relay controls on that board.
Form Factor
The RF200 SNAP Engine is the SNAP Engine based on the ATMEL ATmega128RFA1.
IO pins
The RF200 supports 20 GPIO pins, one more than the original RF100 SNAP Engine. GPIO_19 is
available on pin 22 of the SNAP Engine.
Sleep
The RF200 includes a 32kHz crystal RTC, so for most efficient sleep you should use sleep mode 1.
Wakeup pins
Nine of the IO pins can be used to wake a sleeping engine: pins 2-5 (GPIO_0-GPIO_3), pins 7-10
(GPIO_5-GPIO_8), and pin 12 (GPIO_10). Using pins 7, 8, or 12 (GPIO_5, GPIO_6, or GPIO_10) as
an edge-triggered wakeup signal will work, but will result in higher power consumption.
Analog inputs
Seven of the IO pins support Analog Input: pins 13-15 and pins 17-20.
UART0
Four pins support UART 0: pins 5-8 (GPIO_3-GPIO_6). If you do not need RTS/CTS signals, then 7
and 8 are available for other usage.
UART1
Four pins support UART 1: pins 9-11 (GPIO_7-GPIO_10). If you do not need RTS/CTS signals, then
IO 10 and 11 are available for other usage.
SPI
Three pins can optionally be used for SPI: pins 14-16 (GPIO_12-GPIO_14) are MISO, SCLK and
MOSI. These are not the hardware SPI pins. SNAPpy SPI is done via software emulation.
You will also need one “SPI Chip Select” pin per external SPI device. Any available IO pin can be
used for this purpose.
I
2
C
Two pins can optionally be used for I
2
C: pins 19 and 20 (GPIO_17 and GPIO_18). These are not the
hardware I
2
C pins. SNAPpy I
2
C is done via software emulation. These are also not the same pins
used for I
2
C on the ATmega128RFA1 build of the firmware.
Page 162 of 202 SNAP Reference Manual Document Number 600-0007K