R01UH0823EJ0100 Rev.1.00
Page 1225 of 1823
Jul 31, 2019
RX23W Group
36. CAN Module (RSCAN)
RFIGCV[2:0] Bits (Receive FIFO Interrupt Request Timing Select)
These bits are used to specify the fraction of the transmit/receive FIFO buffer (the number of messages is selected by the
setting of the RFDC[2:0] bits) that must be filled for the FIFO buffer to generate a receive interrupt request when the
RFIM bit is set to 0.
When the RFDC[2:0] bits are set to 001b (4 messages), set the RFIGCV[2:0] bits to 001b, 011b, 101b, or 111b. Modify
these bits only in global reset mode.
36.2.35
Receive FIFO Status Register m (RFSTSm) (m = 0, 1)
Note 1. Only 0 can be written to this bit, to clear the flag. Writing 1 does not affect the flag value.
RFEMP Flag (Receive FIFO Buffer Empty Status Flag)
This flag becomes 1 when all messages in the receive FIFO buffer have been read. This flag also becomes 1 when the
RFCCm.RFE bit is 0 or in global reset mode.
This flag becomes 0 when even a single received message has been stored in the receive FIFO buffer.
RFFLL Flag (Receive FIFO Buffer Full Status Flag)
This flag becomes 1 when the number of messages stored in the receive FIFO buffer matches the FIFO buffer depth set
by the RFCCm.RFDC[2:0] bits.
If the number of messages stored in the receive FIFO buffer becomes smaller than the FIFO buffer depth set by the
RFCCm.RFDC[2:0] bits, this flag becomes 0. This flag also becomes 0 when the RFCCm.RFE bit is set to 0 (no receive
FIFO buffer is used) or in global reset mode.
RFMLT Flag (Receive FIFO Message Lost Flag)
This flag becomes 1 when it is attempted to store a new message while the receive FIFO buffer is full. In this case, the
new message is discarded.
This flag becomes 0 in global reset mode or by writing 0 to this flag.
Modify this bit only in global operating mode or global test mode.
Address(es): RSCAN.RFSTS0 000A 8340h, RSCAN.RFSTS1 000A 8342h
b15
b14
b13
b12
b11
b10
b9
b8
b7
b6
b5
b4
b3
b2
b1
b0
—
—
RFMC[5:0]
—
—
—
—
RFIF RFMLT RFFLL RFEMP
Value after reset:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
Bit
Symbol
Bit Name
Description
R/W
b0
Receive FIFO Buffer Empty
Status Flag
0: The receive FIFO buffer contains unread messages.
1: The receive FIFO buffer contains no unread message
(buffer empty).
R
b1
Receive FIFO Buffer Full
Status Flag
0: The receive FIFO buffer is not full.
1: The receive FIFO buffer is full.
R
b2
Receive FIFO Message Lost
Flag
0: No receive FIFO message is lost.
1: A receive FIFO message is lost.
R/(W)
*
b3
Receive FIFO Interrupt
Request Flag
0: No receive FIFO interrupt request is present.
1: A receive FIFO interrupt request is present.
R/(W)
*
b7 to b4
—
Reserved
These bits are read as 0. The write value should be 0.
R/W
b13 to b8
Receive FIFO Unread
Message Counter
The number of unread messages stored in the receive FIFO
buffer is displayed.
R
b15, b14
—
Reserved
These bits are read as 0. The write value should be 0.
R/W