Figure 21-10 shows how a transmit object can be initialized.
Figure 21-10 Initialization of a Transmit ObjectMsgVal | Arb | Data | Mask | EoB | Dir | NewDat | MsgLst | RxIE | TxIE | IntPnd | RmtEn | TxRqst |
---|
1 | appl. | appl. | appl. | 1 | 1 | 0 | 0 | 0 | appl. | 0 | appl. | 0 |
- The arbitration bits (ID[28:0] and Xtd bit) are
given by the application. The arbitration bits define the
identifier and type of the outgoing message. If an 11-bit
Identifier (standard frame) is used (Xtd = 0), the
Identifier is programmed to ID[28:18]. In this case,
ID[17:0] can be ignored.
- The data registers (DLC[3:0] and Data0-7) are
given by the application. TxRqst and RmtEn must not be set
before the data is valid.
- If the TxIE bit is set, the IntPnd bit is set
after a successful transmission of the message object.
- If the RmtEn bit is set, a matching received
remote frame causes the TxRqst bit to be set; the remote
frame is autonomously answered by a data frame.
- The Mask bits (Msk[28:0], UMask, MXtd, and MDir
bits) can be used (UMask = 1) to allow groups of remote
frames with similar identifiers to set the TxRqst bit. The
Dir bit must not be masked. For details, see Section 21.11.8. Identifier masking must be disabled (UMask = 0) if no
remote frames are allowed to set the TxRqst bit (RmtEn =
0).