User's Manual

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RADIO_INHIBIT: RADIO_INHIBIT provides a mechanism for an external device to temporarily disable
radio operation. Failure to observe the timing requirements defined in the RADIO_INHIBIT AC
Characteristics section may result in unreliable network operation. In designs where the
RADIO_INHIBIT function is not needed. The input must either be tied, pulled or actively driven low to
avoid excess leakage.
TMS, TCK, TDI, TDO: JTAG Port Supporting Software Debug and Boundary Scan.
SLEEPn: The SLEEPn function is not currently supported in software. The SLEEPn input must either be
tied, pulled or actively driven high to avoid excess leakage.
UART_RX, UART_RX_RTSn, UART_RX_CTSn, UART_TX, UART_TX_RTSn, UART_TX_CTSn: The API UART
interface includes bidirectional wake up and flow control. Unused input signals must be driven or pulled
to their inactive state.
TIMEn: Strobing the TIMEn input is the most accurate method to acquire the network time maintained
by WSM2400. WSM2400 latches the network time stamp with sub-microsecond resolution on the rising
edge of the TIMEn signal and produces a packet on the API serial port containing the timing information.
UARTC0_RX, UARTC0_TX: The CLI UART provides a mechanism for monitoring, configuration and
control of WSM2400 during operation.
GPIO3, GPIO4, GPIO5, GPIO6, GPIO20, GPIO21, GPIO22, GPIO23, GPIO26: General purpose I/Os that
can be sampled or driven as described in the Signal/Data Acquisition and Control section.
FLASH_P_ENn, IPCS_SSn, IPCS_SCK, IPCS_MISO, IPCS_SSn: The In-Circuit Programming Control System
(IPCS) bus enables in-circuit programming of WSM2400’s flash memory. IPCS_SCK is a clock and should
be terminated appropriately for the driving source to prevent overshoot and ringing.
OPERATION
The 505-10368-00/505-10369-00 is the world’s most energy efficient IEEE 802.15.4 compliant platform,
enabling battery and energy harvested applications. With a powerful 32-bit ARM Cortex-M3, best-in-
class radio, flash, RAM and purpose-built peripherals, WSM2400 provides a flexible, scalable and robust
networking solution for applications demanding minimal energy consumption and data reliability in
even the most challenging RF environments.
Shown in Figure 19, WSM2400 integrates purpose-built peripherals that excel in both low operating-
energy consumption and the ability to rapidly and precisely cycle between operating and low-power
states. Items in the gray shaded region labeled Analog Core correspond to the analog/RF components.