SMARTRFTRXEBK: Connecting an External MCU - Obtaining GPIO values via SPI Polling of the GPIO_STATUS register

Sudesh Sheodass

Part Number: SMARTRFTRXEBK
Other Parts Discussed in Thread: CC1175

With reference to CC112X/CC1175 Low-Power High Performance Sub-1 GHz RF Transceivers/Transmitter Users Guide (SWRU295E), section 8.5 Packet Handling in Firmware:

The external MCU board I'm connecting to the TRXEB, does not have a interrupt pin to connect to GPIO0. I want to use SPI Polling to read the GPIO status.

Specifically, I'm configuring the GPIO0_CFG for PKT_SYNC_RXTX (0x06).

My questions:

1. What IS the range of values to expect in the GPIO_STATUS.GPIO_STATE field? For instance, if a packet has been transmitted or if it has been received, what values would be expected in the GPIO_STATE field that would map to these states?

2. What is the recommended rate at which this GPIO_STATUS register is polled at?

3. Do you have any sample or reference code demonstrating SPI polling so that I can make reference to?

regards

Sudesh

over 5 years ago

0 TER over 5 years ago

TI__Guru**** 317180 points

All our examples are based on interrupt based packet handling.

In this case reading out RX_NUMBYTES and TX_NUMBYTES would be an option. Any reason why you would like to use GPIO_STATUS instead?

0 Sudesh Sheodass over 5 years ago in reply to TER

Intellectual 680 points

I just thought that it would be easier to use GPIO status since we already have a working driver on another platform that users interrupts. We porting this code and would like to make minimal changes to it.

So in any case, what are the range of values for GPIO STATUS?

0 TER over 5 years ago in reply to Sudesh Sheodass

TI__Guru**** 317180 points

GPIO_STATUS[3] - GPIO3

GPIO_STATUS[2] - GPIO2

etc

Meaning that the bit fields is mapped to each GPIO.

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SMARTRFTRXEBK: Connecting an External MCU - Obtaining GPIO values via SPI Polling of the GPIO_STATUS register