Z1-Feshie
Hardware
The Z1-Feshie platform consists of a Zolertia Z1 and a CC1120 radio module. The CC1120 is connected to the Z1's SPI bus, which is shared with a CC2420 2.4GHz radio and a ST M25P16 16Mbit flash. The CC2420 can be disabled by clearing P4.4 (CC2420 VREG_EN), setting P4.6 (CC2420 !RESET) and setting P3.0 (CC2420 CSn).
The CC1120's is connected to the Z1 as shown in the table below.
CC1120 Pin | MSP430 Pin | Z1 Header | Z1 Header Pin | Function |
---|---|---|---|---|
MOSI | P3.1 | Communications (JP1B) | 36 | SPI Master Out |
MISO | P3.2 | Communications (JP1B) | 38 | SPI Master In |
SCLK | P3.3 | Communications (JP1B) | 34 | SPI Clock |
CSn | P2.1 | Digital (JP1C) | 48 | SPI Slave Select, active low |
!RESET | P2.6 | Digital (JP1C) | 43 | Reset pin, active low |
GPIO0 | P1.0 | Digital (JP1C) | 54 | RX Interrupt trigger |
GPIO2 | ||||
GPIO3 | P4.3 | Digital (JP1C) | 42 | CCA_STATUS |
Radio Driver
The Z1-Feshie platform uses the cc1120_driver Contiki Radio Driver. This driver has been heavily modified from the driver included in Thingsquare Mist as the Mist driver includes a significant number of issues when moved to Contiki that meant it did not function as required. The Mist driver also fails to function with Mist and the TRXEB1120 development kit (a Mist-supported platform).
The CC1120 status is obtained by sending a "SNOP" (no-operation strobe) as this is more efficient than reading the MARCSTATE register.
6LowPAN Network
(from thingsquare kit quide)
RPL routing: ETX measures the stability of the network (128 is "stable") ETX increases with packet loss - so we should track it. PLus the rank shows how far from the gateway the node is. How will we access these metrics?
RPL beacon interval - a stable net rate is 2100s This may need changing for our network?