S2-LP datasheet(73/90 Pages) STMICROELECTRONICS

73 / 90 page

S2-LP

MCU interface

DocID029944 Rev 1

73/90

Bit

Events group

Interrupt event

CRC error

TX FIFO underflow/overflow error

RX FIFO underflow/overflow error

TX FIFO almost full

TX FIFO almost empty

RX FIFO almost full

RX FIFO almost empty

Max. number of back-off during CCA

Signal quality related

Valid preamble detected

Sync word detected

RSSI above threshold (CS)

Device status related

Wake-up timeout in LDCR mode(1)

READY(2)

STANDBY state switching in progress

Low battery level

Power-on reset

Timer related

RX timer timeout

Sniff timer timeout

Notes:

(1)The interrupt flag n.15 is set (and consequently the interrupt request) only when the XO clock is available for the

state machine. This time may be delayed compared to the actual timer expiration. However, the real time event

can be sensed putting the end-of-counting signal on a GPIO output.

(2)The interrupt flag n.16 is set each time the S2-LP goes to READY state and the XO has completed its setting

transient (XO ready condition detected).

All interrupts are reported on a set of interrupt status registers and are individually

maskable. The interrupt status register must be cleared upon a read event from the MCU.

The status of all the interrupts are reported in the IRQ_STATUS register: bits are high for

the events that have generated any interrupts. The interrupts are individually maskable

using the IRQ_MASK registers: if the mask bit related to a particular event is programmed

at 0, that event does not generate any interrupt request.

S2-LP Datasheet(PDF) 73 Page - STMicroelectronics