Rainbow Electronics T89C51CC01 - Manual (Page 87)

87
T89C51CC01
Rev. D – 17-Dec-01
Table 39. CANGSTA Register
CANGSTA (S:AAh)
CAN General Status Register
Note: 1. These fields are Read Only.
Reset Value: x0x0 0000b
7 6 5 4 3 2 1 0
- OVFG - TBSY RBSY ENFG BOFF ERRP
Bit
Number
Bit
Mnemonic Description
7 -
Reserved
The values read from this bit is indeterminate. Do not set this bit.
6 OVFG
Overload frame flag (1)
This status bit is set by the hardware as long as the produced overload frame is
sent.
This flag does not generate an interrupt
5 -
Reserved
The values read from this bit is indeterminate. Do not set this bit.
4 TBSY
Transmitter busy (1)
This status bit is set by the hardware as long as the CAN transmitter generates a
frame (remote, data, overload or error frame) or an ack field. This bit is also
active during an InterFrame Spacing if a frame must be sent.
This flag does not generate an interrupt.
3 RBSY
Receiver busy (1)
This status bit is set by the hardware as long as the CAN receiver acquires or
monitors a frame.
This flag does not generate an interrupt.
2 ENFG
Enable on-chip CAN controller flag (1)
Because an enable/disable command is not effective immediately, this status bit
gives the true state of a chosen mode.
This flag does not generate an interrupt.
1 BOFF
Bus off mode (1)
see Figure 36
0 ERRP
Error passive mode (1)
see Figure 36