upd70f3402 Renesas Electronics Corporation., upd70f3402 Datasheet - Page 637

• Manufacturer Part Number: upd70f3402
• Description: 32-/16-bit Single-chip Microcontroller With Can Interface
• Manufacturer: Renesas Electronics Corporation.

Remarks: 1. If the automatic block transmission request bit CnGMABT.ABTTRGbit is set to 1 in the
1 (high)
Priority
5 (low)
2
3
4
Value of first 11 bits of ID
[ID28 to ID18]:
Frame type
ID type
Value of lower 18 bits of
ID
[ID17 to ID0]:
Message buffer number
2. n = 0, 1
normal operation mode with ABT, the TRQ bit is set to 1 only for one message buffer in
the ABT message buffer group.If the ABT mode was triggered by the ABTTRG bit (1),
one TRQ bit is set to 1 in the ABT area (buffers 0 to 7). In addition to this TRQ bit, the
application can request transmissions (set TRQ bit to 1) for other TX-message buffers
that do not belong to the ABT area. In that case an internal arbitration process (TX-
search) evaluates all of the TX-message buffers with the TRQ bit set to 1 and chooses
the message buffer that contains the highest prioritized identifier for the next transmis-
sion. If there are 2 or more identifiers that have the highest priority (i.e. identical identifi-
ers), the message located at the lowest message buffer number is transmitted
first.Upon successful transmission of a message frame, the following operations are
performed.
•
•
•
m = 0 to 31
Conditions
The TRQ flag of the corresponding transmit message buffer is automatically cleared
to 0.
The transmission completion status bit CINTS0 of the CnINTS register is set to 1
(if the interrupt enable bit (IE) of the corresponding transmit message buffer is set
to 1).
An interrupt request signal INTRRX1 is output (if the CIE0 bit of the CnIE register is
set to 1 and if the interrupt enable bit (IE) of the corresponding transmit message
buffer is set to 1).
User’s Manual U16702EE3V2UD00
Chapter 16 FCAN Controller
The message frame with the lowest value represented by the first 11 bits
of the ID is transmitted first. If the value of an 11-bit standard ID is equal to
or smaller than the first 11 bits of a 29-bit extended ID, the 11-bit standard
ID has a higher priority than a message frame with a 29-bit extended ID.
A data frame with an 11-bit standard ID (RTR bit is cleared to 0) has a
higher priority than a remote frame with a standard ID and a message
frame with an extended ID.
A message frame with a standard ID (IDE bit is cleared to 0) has a higher
priority than a message frame with an extended ID.
If one or more transmission-pending extended ID message frame has
equal values in the first 11 bits of the ID and the same frame type (equal
RTR bit values), the message frame with the lowest value in the lower 18
bits of its extended ID is transmitted first.
If two or more message buffers request transmission of message frames
with the same ID, the message from the message buffer with the lowest
message buffer number is transmitted first.
Description
637