docs(stm32/can): add default filter and FIFO mapping section for CAN and CAN FD

Author: Jiu-xiao

docs/code_gen/stm32/can.md

@@ -8,6 +8,22 @@ sidebar_position: 10
 
 LibXR 支持标准 CAN 和 CAN FD。在 STM32CubeMX 中需要启用相应的外设和中断，并至少为标准帧和扩展帧分配一个过滤器。
 
+## 默认过滤器与FIFO配置
+
+LibXR会为每个CAN/CANFD的标准帧和扩展帧各配置一个默认过滤器，允许所有数据帧通过。
+
+对于不同CAN/CANFD数量的平台，FIFO的配置如下：
+
+| 经典CAN | CAN1 | CAN1+CAN2 | CAN1+CAN2+CAN3 |
+| ------- | ---- | --------- | -------------- |
+| FIFO0   | CAN1 | CAN1      | CAN1+CAN2      |
+| FIFO1   | N/A  | CAN2      | CAN3           |
+
+| CAN FD | CANFD1 | CANFD1+CANFD2 | CANFD1+CANFD2+CANFD3 |
+| ------ | ------ | ------------- | -------------------- |
+| FIFO0  | CANFD1 | CANFD1        | CANFD1               |
+| FIFO1  | N/A    | CANFD2        | CANFD2+CANFD3        |
+
 ## 示例
 
 第二个参数表示发送队列大小，用于缓冲待发送的数据帧。

i18n/en/docusaurus-plugin-content-docs/current/code_gen/stm32/can.md

@@ -8,6 +8,22 @@ sidebar_position: 10
 
 LibXR supports both standard CAN and CAN FD. You need to enable the respective peripherals and interrupts in STM32CubeMX, and allocate at least one filter for both standard and extended frames.
 
+## Default Filters and FIFO Configuration
+
+LibXR configures one default filter for each CAN/CAN FD controller, separately for standard and extended frames, allowing all data frames to pass through.
+
+The FIFO configuration for different numbers of CAN/CAN FD controllers is as follows:
+
+| Classic CAN | CAN1 | CAN1+CAN2 | CAN1+CAN2+CAN3 |
+| ----------- | ---- | --------- | -------------- |
+| FIFO0       | CAN1 | CAN1      | CAN1+CAN2      |
+| FIFO1       | N/A  | CAN2      | CAN3           |
+
+| CAN FD | CANFD1 | CANFD1+CANFD2 | CANFD1+CANFD2+CANFD3 |
+| ------ | ------ | ------------- | -------------------- |
+| FIFO0  | CANFD1 | CANFD1        | CANFD1               |
+| FIFO1  | N/A    | CANFD2        | CANFD2+CANFD3        |
+
 ## Example
 
 The second parameter represents the transmission queue size, which buffers outgoing messages.