When the DCAN_TEST[9] RDA bit is set while the DCAN module is in test mode (DCAN_CTL[7] TEST = 1), the software has direct access to the message RAM. Due to the 32-bit bus structure, the RAM is split into word lines to support this feature. The software has access to one word line at a time only.
In RAM direct access mode, the RAM is represented by a continuous memory space within the address frame of the DCAN module, starting at the message RAM base address.
Note: During direct access mode, the message RAM cannot be accessed via the IFx register sets.
Any read or write to the RAM addresses for RAM Direct Access during normal operation mode (TEST bit or RDA bit not set) will be ignored.
Table 24-750 Message RAM Representation in RAM Direct Access Mode 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
DATA_4 | DATA_5 | DATA_6 | DATA_7 |
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
DATA_0 | DATA_1 | DATA_2 | DATA_3 |
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
ID[27:0] | DLC[3:0] |
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Msk[28:0] | Xtd | Dir | ID[28] |
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
RESERVED | Parity[4:0] | Unused | MsgLst | UMask | TxIE | RxTE | RmtEn | EOB | MXtd | MDir |
Note: Writes to unused bits have no effect.