Function Headers and Description
10.2 Status Functions
10.2.1 Echo_DriverStatus
tECHO_STATUS Echo_DriverStatus(void);
Syntax:
Parameters: None
Return:
16-bit flag word indicating the status of the driver.
Description: Indicates the status of the device driver via the bit flags returned. The format of the status
word is detailed in Section 8, “Status Word.”
Notes:
This service must be called before attempting to read from the Rx buffer to ensure there is
valid data in the buffer at echoNextMessage(if a message has been received).
10.2.2 Echo_ClearError
void Echo_ClearError(void);
Syntax:
Parameters: None
Return:
None
Description: Clears the error and timeout bits.
10.3 Message Sending Functions
10.3.1 Echo_SendPreambleID
void Echo_SendPreambleID(void);
Syntax:
Parameters: None
Return:
None
Description: Switches to transmit mode and initiates sending a message consisting of a preamble
sequence followed by the target device ID. The ID is read from the ID byte in the Tx buffer,
with the number of bits defined by the ECHO_ID_LENGTHconfiguration option. During
transmission, the status flag BusyTx is set.
Notes:
If ECHO_ID_LENGTHis less than eight, the ID should reside in the bottom ECHO_ID_LENGTH
bits of the ID byte. This service does not switch back to receive mode and should be used
with the Echo_SendData() service to send complete messages and return to receive mode
(see Figure 8). Before using this function to switch driver mode (both banks are enabled),
the right bank of registers must be set by Echo_ChangeBank(ECHO_BANK_x).
Software Drivers for MC33696, Rev. 1
20
Freescale Semiconductor
FREESCALE [ Freescale ]
