SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
If a frame write access for any VBUF begins from its virtual frame start address without a CBUF software reset and the last write address is not the virtual frame end address or is in the last CBUF slice, then the previous frame is considered to be short. This includes the case where a new frame write happens twice without a new frame read in between, which is an indication of an extremely short frame. When a short frame event is detected, the OCM controller generates a short frame detection interrupt and temporarily disables overflow checking on the write access, including also the current access, until a frame read happens in order to avoid false overflow indication on a suspended read side following the short frame detection.
If the last write address is in the last CBUF slice the short frame detection can be ignored if the CFG_OCMC_CBUF_ERR_HANDLER[1] SHORT_FRAME_PREV_EOF_SEL bit is set to 0x1.
The STATUS_CBUF_SHORT_FRAME_DETECT[11:0] CBUF_ERR bit field has status flags to indicate a short frame detection for each CBUF. When a short frame condition occurs the corresponding bit is set to 0x1.
The INTR0_STATUS_RAW_SET[14] CBUF_SHORT_FRAME_DETECT_FOUND/INTR1_STATUS_RAW_SET[14] CBUF_SHORT_FRAME_DETECT_FOUND bit is asserted if at least one of the bits in the STATUS_CBUF_SHORT_FRAME_DETECT[11:0] CBUF_ERR bit field is set to 0x1.
In addition, the short frame detection enabling/disabling is controlled by the CFG_OCMC_CBUF_ERR_HANDLER[0] SHORT_FRAME_DETECT_CHECK_EN bit.