6.2 Configuring the GPIOs
The GPIO configuration can be found under the GPIOs section. By default, GPIO0 and GPIO1 are used by the Packet Trace interface
on packet-based examples. To configure GPIO0 and 1, turn on this profile.
Figure 6.4. Packet Trace Interface Plugin
Note:
On high-power designs using switched matching, it is not recommended to change GPIO2 and GPIO3 since they’re controlling
the RF switch.
Radio GPIOs are very useful for debugging problems. Some useful settings:
• Outputs TX Data bits pulled from the TX FIFO
• Outputs the demodulated RX Data stream
• Outputs TX or RX data CLK
• This output is set high while in TX state
• This output is set high while in RX state
• This output goes high when a valid preamble is detected and returns low after the packet is received
• This output goes high when the chip is NOT in SLEEP state
For example, the following profile can be used to optimize for power consumption:
Figure 6.5. GPIO Configuration for Power Optimization
• GPIO0 is high when the radio is not sleeping
• GPIO1 is high when transmitting
• GPIO2 is high when the radio is in receive mode
• GPIO3 is high when the radio is receiving a packet
After compiling and uploading, the program should use the modified configuration. The GPIOs can be found on P30, P31, P32 and P33
on the WSTK. GPIO2 and GPIO3 are directly wired on all kits, GPIO0 and GPIO1 is directly wired on the EZR32HG kits, but only usa-
ble through PRS channels on EZR32LG and EZR32WG kits. To configure the PRS channels, see the “EZRadio and EZRadioPRO
Transceivers GPIO Configuration” in the data sheet.
AN888: EZR32 Quick Start Guide
Modifying the Radio Configuration
silabs.com
| Smart. Connected. Energy-friendly.
Rev. 0.4 | 16
