Equation for Can Traffic

docs/docs/firmware/can-traffic.md

@@ -0,0 +1,46 @@
+
+# Calculating CAN traffic
+
+In order to calculate the CAN load, we must declare a few variables and their importance within the CAN protocol.
+
+## Baud (kbaud)
+
+The baud rate is the rate at which data is transfered in a communication channel (like CAN). For example, 9600 Baud rate is 9600 bits per second
+
+## Frequency (Hz)
+
+Frequency is the number of messages transmitted per second for each message type. Different messages can have different frequencies.
+
+This variation affects the total bits transferred and, in turn, the bus load. To calculate bits per second, consider each message’s frequency and whether their lengths differ.
+
+## Total Data Per Cycle
+
+Total data per cycle includes all the bits transmitted in one CAN message. This includes the payload and overhead bits like the start of frame, CRC, acknowledgment, control field, etc.
+
+## The bus load is determined by
+
+$$
+\text{Total Bits Per Second} = \sum_{i=1}^n \left(\text{Frequency}_i \times \text{Message Length}_i\right)
+$$
+
+$$
+\text{Bus Load (%)} = \frac{\text{Total Bits per Second}}{\text{Baud Rate}} \times 100
+$$
+
+## Sample calculation
+
+**Given**:
+
+Battery Status: Frequency = 100Hz, Length = 400 bits
+
+Motor Control: Frequency = 50Hz, Length = 100 bits
+
+Baud Rate: 500 kbaud (500,000 bits transferred per second)
+
+$$
+\text{Total Bits Per Second} = (100 \times 400) + (50 \times 100) = 40,000 + 5,000 = 45,000 \text{ bits per second}
+$$
+
+$$
+\text{Bus Load} = \left(\frac{45,000}{500,000}\right) \times 100 = 9\%
+$$

docs/docs/firmware/javascripts/katex.js

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docs/mkdocs.yml

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+extra_javascript:
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+  - https://unpkg.com/mathjax@3/es5/tex-mml-chtml.js
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 copyright: Copyright © McMaster Formula Electric
 
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 repo_url: https://github.com/macformula/racecar
 repo_name: macformula/racecar
@@ -123,6 +129,7 @@ nav:
     - firmware/architecture.md
     - firmware/project-structure/index.md
     - firmware/compile-project.md
+    - firmware/can-traffic.md
   - Glossary: glossary.md
 
 watch: