Analog Devices ADSP-SC58 Series Hardware Reference Manual page 1306

ADSP-SC58x CAN Register Descriptions
Universal Counter Reload/Capture Register
The register holds the period value (universal count), which is used in auto-transmit mode as the peri-
CAN_UCRC
od for sending the message in mailbox 11 (broadcast heartbeat) to all CAN nodes. Accordingly, messages sent this
way usually have high priority.
The period value is written to the
(CAN_UCCNF.UCCNF = 0x3), the CAN loads the counter with the value in CAN_UCRC. The counter decrements
to 0 at the CAN bit clock rate, then is reloaded. Each time the counter decrements to 0, the CAN sets the
CAN_TRS1.MB bit for mailbox 11 and sends the corresponding message from mailbox 11.
Note that for auto-transmit mode, mailbox 11 must be configured as a transmit mailbox and must contain valid
data (identifier, control bits, and data). This setup must occur before the counter first expires after this mode is ena-
bled.
Figure 25-64: CAN_UCRC Register Diagram
Table 25-59: CAN_UCRC Register Fields
Bit No.
(Access)
15:0 UCVAL
(R/W)
25–90
register. When auto-transmit mode is enabled
CAN_UCRC
15 14 13
0 0 0
UCVAL (R/W)
Universal Counter Value
Bit Name
Universal Counter Value.
The CAN_UCRC.UCVAL bits hold the value for the universal count period, which is
used in auto-transmit mode.
ADSP-SC58x/ADSP-2158x SHARC+ Processor Hardware Reference
12 11 10 9 8 7 6 5
0 0 0 0 0 0 0 0
Description/Enumeration
4 3 2 1 0
0 0 0 0 0