MOD5234-100IR NetBurner Inc, MOD5234-100IR Datasheet - Page 483

• Manufacturer Part Number: MOD5234-100IR
• Description: MOD5234 10/100 ETHERNET MODULE
• Manufacturer: NetBurner Inc
• Type: Controllers & Processorsr

Specifications of MOD5234-100IR

• Interface: I²C, SPI, UART
• Voltage - Supply: 2.5V
• Mounting Type: Surface Mount
• Package / Case: Module
• Product: Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Format: -
• Baud Rates: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: Q4483564

21.4.6 CAN Protocol Related Frames
21.4.6.1 Remote Frames
The remote frame is a message frame which is transmitted to request a data frame. The FlexCAN
can be configured to transmit a data frame automatically in response to a remote frame, or to
transmit a remote frame and then wait for the responding data frame to be received.
When transmitting a remote frame, the user initializes a message buffer as a transmit message
buffer with the RTR bit set. Once this remote frame is transmitted successfully, the transmit
message buffer automatically becomes a receive message buffer, with the same ID as the remote
frame that was transmitted.
When a remote frame is received by the FlexCAN, the remote frame ID is compared to the IDs of
all transmit message buffers programmed with a CODE of 1010. If there is an exact matching ID,
the data frame in that message buffer is transmitted. If the RTR bit in the matching transmit
message buffer is set, the FlexCAN will transmit a remote frame as a response.
A received remote frame is not stored in a receive message buffer. It is only used to trigger the
automatic transmission of a frame in response. The mask registers are not used in remote frame ID
matching. All ID bits (except RTR) of the incoming received frame must match for the remote
frame to trigger a response transmission. The matching message buffer immediately enters the
internal arbitration process, but is considered as a normal Tx MB, with no higher priority. The data
length of this frame is independent of the data length code (DLC) field in the remote frame that
initiated its transmission.
21.4.6.2 Overload Frames
Overload frame transmissions are not initiated by the FlexCAN unless certain conditions are
detected on the CAN bus. These conditions include:
Freescale Semiconductor
• Detection of a dominant bit in the first or second bit of intermission.
• Detection of a dominant bit in the seventh (last) bit of the end-of-frame (EOF) field in
• Detection of a dominant bit in the eighth (last) bit of the error frame delimiter or overload
receive frames.
frame delimiter.
Deactivation takes precedence over locking. If the CPU deactivates a
locked Rx MB, then its lock status is negated, and the MB is marked
as invalid for the current matching round. Any pending message on
the SMB will not be transferred to the MB anymore.
MCF5235 Reference Manual, Rev. 2
NOTE
Functional Overview
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