I'm the process of implementing the rolling buffer for the ADF7024. But there's an ambiguity in the Rolling Data Buffer app note (AN-1317, rev0). Table 1. refers to BB_TX/RX_BUFFER_SIGNAL as a location however, later in the app note, Figures 1 and 2 refer to BB_TX/RX_BUFFER_SIGNAL as length values.
So which is it? Does BB_TX_BUFFER_SIGNAL refer an address in the PACKET RAM or does it represent the length of the signal?
This will help me greatly by halving the amount of troubleshooting. Thanks!
There are two types of interrupt that you could have when using rolling buffers: (1) INTERRUPT_BUFFER_FULL, and (2) INTERRUPT_BUFFER_ALMOST_FULL.
BB_TX_BUFFER_SIZE holds the length or size…
BB_TX_BUFFER_SIZE holds the length or size of the buffer. When the end of the buffer is reached (PKT_TX_BASE_ADR + BB_TX_ BUFFER_SIZE), the INTERRUPT_BUFFER_FULL is asserted.
Now, the BB_TX_ BUFFER_SIGNAL should be set as to when you want the INTERRUPT_BUFFER_ALMOST_FULL is asserted. Example, if you want this interrupt asserted upon reaching the half of the buffer, then BB_TX_ BUFFER_SIGNAL should be set as
BB_TX_ BUFFER_SIGNAL = BB_TX_BUFFER_SIZE/2
Hope this helps.