SPRUJ42E March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
PRODUCTION DATA
A and B byte count
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Instance Name | Physical Address |
---|---|
EDMA0 | 52A0 4008h |
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 |
BCNT | |||||||
R/W | |||||||
0h | |||||||
23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
BCNT | |||||||
R/W | |||||||
0h | |||||||
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 |
ACNT | |||||||
R/W | |||||||
0h | |||||||
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
ACNT | |||||||
R/W | |||||||
0h |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
31:16 | BCNT | R/W | 0h | BCNT : Count for 2nd Dimension: BCNT is a 16-bit unsigned value that specifies the number of arrays of length ACNT. For normal operation valid values for BCNT can be anywhere between 1 and 65535. Therefore the maximum number of arrays in a frame is 65535 [64K-1 arrays]. BCNT=1 means 1 array in the frame and BCNT=0 means 0 arrays in the frame. In normal mode a BCNT of '0' is considered as either a Null or Dummy transfer. A Dummy or Null transfer will generate a Completion code depending on the settings of the completion bit fields of the OPT field. If the OPT.WIMODE bit is set then the programmed BCNT value will be incremented by '1' before submission to TC. I.e. 0 means 1 1 means 2 2 means 3 ... |
15:0 | ACNT | R/W | 0h | ACNT : number of bytes in 1st dimension: ACNT represents the number of bytes within the first dimension of a transfer. ACNT is a 16-bit unsigned value with valid values between 0 and 65535. Therefore the maximum number of bytes in an array is 65535 bytes [64K-1 bytes]. ACNT must be greater than or equal to '1' for a TR to be submitted to TC. An ACNT of '0' is considered as either a null or dummy transfer. A Dummy or Null transfer will generate a Completion code depending on the settings of the completion bit fields of the OPT field. If the OPT.WIMODE bit is set then the ACNT field represents a word count. The CC must internally multiply by 4 to translate the word count to a byte count prior to submission to the TC. The 2 MSBs of the 16-bit ACNT are reserved and should always be written as 'b00 by the user. If user writes a value other than 0 it will still be treated as 0 since the multiply-by-4 operation [to translate between a word count and a byte count] will drop the 2 msbits. For dummy and null transfer definition the ACNT definition will disregard the 2 msbits. I.e. a programmed ACNT value of 0x8000 in WI-mode will be treated as 0 byte transfer resulting in null or dummy operation dependent on the state of BCNT and CCNT. |