NXP Semiconductors MC9S12G - Page 587

Scalable Controller Area Network (S12MSCANV3)
MC9S12G Family Reference Manual Rev.1.27
NXP Semiconductors 589
18.3.2.13 MSCAN Reserved Register
This register is reserved for factory testing of the MSCAN module and is not available in normal system
operating modes.
NOTE
Writing to this register when in special system operating modes can alter the
MSCAN functionality.
18.3.2.14 MSCAN Miscellaneous Register (CANMISC)
This register provides additional features.
Module Base + 0x000C Access: User read/write
1
1
Read: Always reads zero in normal system operation modes
Write: Unimplemented in normal system operation modes
76543210
R00000000
W
Reset:00000000
= Unimplemented
Figure 18-16. MSCAN Reserved Register
Module Base + 0x000D Access: User read/write
1
1
Read: Anytime
Write: Anytime; write of ‘1’ clears flag; write of ‘0’ ignored
76543210
R0000000
BOHOLD
W
Reset:00000000
= Unimplemented
Figure 18-17. MSCAN Miscellaneous Register (CANMISC)
Table 18-21. CANMISC Register Field Descriptions
Field Description
0
BOHOLD
Bus-off State Hold Until User Request — If BORM is set in MSCAN Control Register 1 (CANCTL1), this bit
indicates whether the module has entered the bus-off state. Clearing this bit requests the recovery from bus-off.
Refer to Section 18.5.2, “Bus-Off Recovery,” for details.
0 Module is not bus-off or recovery has been requested by user in bus-off state
1 Module is bus-off and holds this state until user request