14.8.8 PHY_CC_CCA
| Name: | PHY_CC_CCA |
| Offset: | 0x08 |
| Reset: | 0x25 |
| Property: | - |
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| CCA_REQUEST | CCA_MODE[1:0] | CHANNEL[4:0] | |||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | |
Bit 7 – CCA_REQUEST CCA_REQUEST
The register bit CCA_REQUEST initiates a manual started CCA measurement.
| Value | Description |
|---|---|
| 0x0 | Reset value |
| 0x1 | Starts a CCA measurement |
- The read value returns always with zero.
- If a CCA request is initiated in states others than RX_ON or RX_BUSY the PHY generates an IRQ_4 (CCA_ED_DONE) and sets the register bit CCA_DONE, however no CCA was carried out.
A manual CCA measurement is initiated with setting CCA_REQUEST = 1. The end of the CCA measurement is indicated by interrupt IRQ_4 (CCA_ED_DONE). Register bits CCA_DONE and CCA_STATUS (register 0x01, TRX_STATUS) are updated after a CCA_REQUEST. The register bit is automatically cleared after requesting a CCA measurement with CCA_REQUEST = 1.
Bits 6:5 – CCA_MODE[1:0] CCA_MODE
The CCA mode can be selected using register bits CCA_MODE.
| Value | Description |
|---|---|
| 0x0 | Mode 3a, Carrier sense OR energy above threshold |
| 0x1 | Mode 1, Energy above threshold |
| 0x2 | Mode 2, Carrier sense only |
| 0x3 | Mode 3b, Carrier sense AND energy above threshold |
- IEEE 802.15.4–2006 CCA mode 3 defines the logical combination of CCA mode 1 and 2 with the logical operators AND or OR.
- If register bit CSMA_LBT_MODE is set, CCA_MODE configures the LBT measurement.
Bits 4:0 – CHANNEL[4:0] CHANNEL
The register bits CHANNEL define the RX/TX channel. The channel assignment is according to IEEE 802.15.4.
| Value | Description |
|---|---|
| 0x00 | 868.3MHz |
| 0x01 | 906MHz |
| 0x02 | 908MHz |
| 0x03 | 910MHz |
| 0x04 | 912MHz |
| 0x05 | 914MHz |
| 0x06 | 916MHz |
| 0x07 | 918MHz |
| 0x08 | 920MHz |
| 0x09 | 922MHz |
| 0x0A | 924MHz |
| Reserved | All other values are reserved |