Datasheet

www.ti.com FlexRay Module Registers
26.3.2.5 Message Buffer Control Registers
26.3.2.5.1 Message RAM Configuration (MRC)
The message RAM Configuration register defines the number of message buffers assigned to the static
segment, dynamic segment, and FIFO. The register can be written during DEFAULT_CONFIG or CONFIG
state only.
Figure 26-158 and Table 26-143 illustrate this register.
Figure 26-158. Message RAM Configuration Register (MRC) [offset_CC = 300h]
31 27 26 25 24 23 16
Reserved SPLM* SEC* LCB*
R-0 R-1 R-0 R/W-80h
15 8 7 0
FFB* FDB*
R/W-0 R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset; *These bits can be updated in DEFAULT_CONFIG or CONFIG state
only
Table 26-143. Message RAM Configuration Register (MRC) Field Descriptions
Bit Field Value Description
31-27 Reserved 0 Read returns 0. Writes have no effect.
26 SPLM Sync Frame Payload Multiplex. This bit is only evaluated if the node is configured as sync node
(SUCC1.TXSY = 1) or for single slot mode operation (SUCC1.TSM = 1). When this bit is set to 1
message buffers 0 and 1 are dedicated for sync frame transmission with different payload data on
channel A and B. When this bit is set to 0, sync frames are transmitted from message buffer 0 with
the same payload data on both channels. Note that the channel filter configuration for message
buffer 0 resp. message buffer 1 has to be chosen accordingly.
0 Only message buffer 0 locked against reconfiguration
1 Both message buffers 0 and 1 are locked against reconfiguration
25-24 SEC Secure Buffers. Not evaluated when the communication controller is in DEFAULT_CONFIG or
CONFIG state.
0 Reconfiguration of message buffers enabled with numbers < FFBh enabled
Exception: In nodes configured for sync frame transmission or for single slot mode operation
message buffer 0 (and if SPLM = 1, also message buffer 1) is always locked
1h Reconfiguration of message buffers with numbers < FDB and with numbers FFB locked and
transmission of message buffers for static segment with numbers FDB disabled
2h Reconfiguration of all message buffers locked
3h Reconfiguration of all message buffers locked and transmission of message buffers for static
segment with numbers FDB disabled
26-16 LCB Last configured buffer.
0-7Fh Number of message buffers is LCB + 1
≥ 80h No message buffer configured
15-8 FFB First buffer of FIFO.
0 All message buffers assigned to the FIFO
0-7Fh Message buffers from FFB to LCB assigned to the FIFO
≥ 80h No message buffer assigned to the FIFO
7-0 FDB First dynamic buffer.
0 No group of pure static buffers configured
0-7Fh Message buffers 0 to FDB - 1 reserved for static segment
≥ 80h No dynamic buffers configured
1329
SPNU563–May 2014 FlexRay Module
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated