ML7345 Datasheet, PDF (83/261 Pages) –

FEDL7345/D-02
ML7345/ML7345D
(3) IDLE detection mode
IDLE detection mode continues CCA until IDLE detection. IDLE detection CCA will be executed when RX_ON is issued
while CCA_EN(CCA_CTRL: B0 0x39(4)]) = 0b1, CCA_CPU_EN(CCA_CTRL: B0 0x39(5)]) = 0b0 and CCA_IDLE_EN
(CCA_CTRL: B0 0x39(6)]) = 0b1 are set.
Like normal mode, CCA judgment is determined by average ED value in ED_VALUE([ED_RSLT: B0 0x3A]) and CCA
threshold defined by [CCA_LVL: B0 0x37]. If the averaged ED value exceeds the CCA threshold value, it is determined as
“BUSY”, and CCA_RSLT[1:0]([CCA_CTRL: B0 0x39(1-0)]) = 0b01 is set. If the averaged ED value is smaller than CCA
threshold value for the IDLE detection period defined by IDLE_WAIT[9:0] of the [IDLE_WAIT_L], [IDLE_WAIT_H]: B0
0x3B,0x3C], it is determined as “IDLE”, and CCA_RSLT[1:0] = 0b00 is set. For details operation of IDLE_WAIT[9:0],
please refer to “IDLE detection for longer time period”.
In IDLE detection mode, only when IDLE is detected, CCA completion interrupt INT[18]([INT_SOURCE_GRP3: B0
0x0F(2)]) is generated. Also, if CCA is performed based on the CCA_EN setting, CCA_EN(CCA_CTRL: B0 0x39(4)]) and
CCA_IDLE_EN(CCA_CTRL: B0 0x39(6)]) are automatically cleared to 0b0.
In IDLE detection mode, while BUSY is detected, CCA completion interrupt INT[18]([INT_SOURCE_GRP3: B0
0x0F(2)]) is not generated, and IDLE detection continues. Upon clearing CCA completion interrupt
INT[18]([INT_SOURCE_GRP3: B0 0x0F(2)]), CCA_RSLT[1:0] are reset to 0b00. Therefore, CCA_RSLT[1:0] should be
read before clearing CCA completion interrupt INT[18]([INT_SOURCE_GRP3: B0 0x0F(2)]).
If an ED value exceeds the value defined by [CCA_IGNORE_LVL: B0 0x36], as long as a given ED value is included in
the averaging target of ED value calculation, IDLE judgment is not performed. In this case, if the averaged ED value is
smaller than [CCA_LVL: B0 0x37], IDLE determination is not performed and CCA_RSLT[1:0] indicates 0b11. CCA
operation continues until given ED value is out of averaging target and “IDLE” is determined. For detail behavior when the
ED value exceeds [CCA_IGNORE_LVL: B0 0x36], refer to “ IDLE determination exclusion under strong signal input “.
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