AN633
Rev. 0.7
25
8.2. Radio Chip Waking Up
First, the radio is in the off state. After the SDN pin is pulled low, the radio wakes up and performs a Power on
Reset which takes a maximum of 6 ms (900 µs typical at room temperature) until the chip is ready to receive
commands on the SPI bus. The GPIO1 pin goes high when the radio is ready for receiving SPI commands. During
the reset period, the radio cannot accept any SPI commands. There are two ways to determine if the chip is ready
to receive SPI commands after a reset event. Either use a timer in the host microcontroller to wait or connect the
GPIO1 pin of the radio to the host MCU and poll the status of this pin. During power on reset, it remains low. Once
the reset is finished, the radio sets the GPIO1 to the high state.
Next, the radio device has to be sent to active mode by issuing a "POWER_UP" command via the SPI interface
which takes approximately 15 ms to be completed. It can be monitored in three ways. If the command is completed
either the GPIO1 pin of the radio goes low by issuing the command and the radio sets it to high state or the NIRQ
pin is asserted or the host MCU can monitor CTS over the SPI.
Figure 21. Radio Wake Up Process
Issue POWER_UP
command over SPI
(GPIO1= )
Clear all interrupts
(GPIO1= )
Wait for max. delay of
POR (<6ms)
CTS ready
over SPI?
nIRQ = ?
GPIO1 = ?
N
Y
Optional
Optional
N
N
N
Y
Y
Y
CTS ready
over SPI?
GPIO1 = ?
GPIO1 = ?
Y
Y
N
N
Optional
Start
2.
Radio Power
On Reset
(POR)
3.
Radio
Boot
1.
Host MCU
Initialization
4.
Radio
Ready
Host MCU applies
SDN pulse
Host MCU
initiates invoking
Radio API
Host MCU clears
Radio interrupts
SDN = 10us
Содержание EZRADIOPRO Si4060
Страница 24: ...AN633 24 Rev 0 7 Figure 20 Supply Current versus Time Diagram from Shutdown to RX State...
Страница 67: ...AN633 Rev 0 7 67 Figure 48 Variable Length Packet Reception Flowchart...
Страница 69: ...AN633 Rev 0 7 69 Figure 50 Packet Matching Reception Flowchart...
Страница 73: ...AN633 Rev 0 7 73 Figure 54 Packet Reception with Automatic RX Hopping Flowchart...
Страница 75: ...AN633 Rev 0 7 75 Figure 56 Packet Reception with Manual Rx Hopping...
Страница 80: ...AN633 80 Rev 0 7 Figure 62 Long Packet Transmission Workflow...
Страница 81: ...AN633 Rev 0 7 81 Figure 63 Long Packet RX Flowchart...