CAN FD v2.0
82
PG223 December 5, 2018
Chapter 4:
Design Flow Steps
-
Sequential (First-In-First-Out)
– The core stores received messages in RX block
RAM in a sequential manner in a 32-deep message space based on the program
ID matching and provides sequential access to the host.
-
Mailbox
– Received messages are stored in buffers based on the ID
programmed in the respective buffer. ID match search starts from RX buffers 0
and incoming messages can be stored in any receive buffers based on the ID
match result. The host can access stored messages in any random order.
•
RX Buffers
– This parameter decides the number of RX buffers enabled for the current
IP instance and is valid and applicable when the RX mode is selected as Mailbox. Valid
values are 16, 32, and 48.
•
RX FIFO-0 Depth
– This parameter defines the depth of RX Buffer FIFO-0. It is valid and
applicable only when selected RX Mode is
Sequential
.
•
Enable RX FIFO-1
– This parameter determines if the IP has a second RX FIFO. It is valid
and applicable only when the selected RX Mode is
Sequential
.
•
RX FIFO-1 Depth
– This parameter defines the depth of RX Buffer FIFO-1. It is valid and
applicable only when the selected RX Mode is
Sequential
.
User Parameters
shows the relationship between the fields in the Vivado IDE and the User
Parameters (which can be viewed in the Tcl console).
Table 4-1:
Vivado IDE Parameter to User Parameter Relationship
Vivado IDE Parameter/Value
User Parameter/Value
Default Value
Processor Interfaces
Valid values are 0 and 1.
C_EN_APB
Valid values are 0 and 1.
1
TX Buffers
Valid values are 8, 16, and 32.
NUM_OF_TX_BUF
Valid values are 8, 16, and 32.
8
RX Mode
Valid values are:
• Sequential
• MailBox
RX_MODE
Valid values are:
• 0 = Sequential
• 1 = MailBox
0
RX Buffers
Valid values are 16, 32, and 48.
NUM_OF_RX_MB_BUF
Valid values are 16, 32, and 48.
16
Note:
This parameter is valid for
RX MailBox mode.
RX FIFO-0 Depth
Valid values are 32 and 64.
C_RX_FIFO_0_DEPTH
Valid values are 32 and 64.
64
Note:
This parameter is valid only
when the IP is in FIFO/Sequential
mode.