XMC1000 TIP of the day: Receive Interrup in USIC module

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
Not applicable
There are several interrupts for receive data in USIC module such as Standard Receive, Alternative Receive, Receive Start, Standard Receive Buffer and Alternative Receive Buffer.
Have you ever wonder how which interrupt you should use and how this interrupt gets trigger?
Here we will explain each of these interrupts.

1) Standard Receive Interrupt
This interrupt indicate a new data is received and becomes available in the receive buffer RBUF.
When this interrupt is triggered, user application can read out the new data from the RBUF register.

2) Alternative Receive Interrupt
This interrupt indicate that a specific data word has been received and it means differently in different communication protocol.
In ASC/UART, this interrupt is triggered when the new received data having parity error.
In SSC/SPI, this interrupt is triggered when the first data word is received.
In IIC/I2C, it indicate the reception of the first byte of a new frame.
In IIS/I2S, it indicatethe WA information. If the received data is WA=1, this interrupt will be triggered, else Standard Recevied will be triggered.

3) Receive Start Interrupt.
This interrupt is triggered when the receive clock edge that shifts in the first bit of a new data word is detected.
This interrupt is only indicate the receiver has start receiving data.
Hence, reading RBUF during this interrupt does not gives you the new receive data.

4) Standard Receive Buffer Interrupt
This is the receive interrupt for FIFO Buffer. The interrupt is triggered when the filling level (or trigger limit in DAVE3) of the Receive FIFO is reached.
When this interrupt is triggered, data can be read out from OUTR register.

5) Alternative Receive Buffer Interrupt
This interrupt does not use in FIFO filling level trigger. This interrupt is used in RCI mode.
The trigger of this interrupt is same as indicated in Alternative Receive Interrupt with only different the data is in receive FIFO.
0 Likes
0 Replies