SI4012 Datasheet, PDF (28/50 Pages) Silicon Laboratories – CRYSTAL-LESS RF TRANSMITTER

Si4012
5.1.9. COMMAND: GET_INT_STATUS
Purpose: Read the interrupt status and clear interrupts.
ARG:
None
DATA:
 iffunder—FIFO Underflow
 itxffafull—TX FIFO Almost Full
 itxffaem—TX FIFO Almost Empty
 iffover—FIFO Overflow
 ipksent—Packet Sent
 ilbd—Low Battery Detect
 itune—tune complete
 ipor—Power On Reset
Command:
GET_INT_STATUS
7
Command
CMD
Response:
6
5
4
3
0x64
2
1
0
GET_INT_STATUS
7
Reply
6
5
4
3
2
1
0
STATUS
CTS
Err
DATA1
iffunder
itxffafull
itxf-
faem
iffover ipksent
ilbd
itune ipor
Notes: Calling the GET_INT_STATUS command will clear all interrupts and reset the nIRQ pin. Therefore, the host must note
any interrupt bits that are set and take the necessary actions to service these interrupts.
TX FIFO Almost Full and TX FIFO Almost Empty Interrupts
These interrupts are triggered upon transition at the respective thresholds. Therefore, if an interrupt is generated for
FIFO Almost Empty and then cleared by a call to GET_INT_STATUS, another interrupt will NOT be generated if the FIFO
remains below the Almost Empty threshold. The FIFO must go above the threshold and then fall back to the threshold
before another Almost Empty threshold is generated and sent to the host.
Low Battery Detect (LBD) Interrupt
The LBD is cleared when the host calls GET_INT_STATUS. The Si4012 regenerates lbd interrupts periodically when the
LBD timer expires.
28
Rev 1.0