NEXUSX use dmar

[sensei-hacker]

User description

A couple minor changes to the NEXUS target based on my testing.

In #11082 (comment)
@functionpointer pointed out that UART3 would only work for a receiver due to the initialization order. One of the two variants already has an onboard receiver on UART5. Defining uart3 may therefore cause confusion more often than its helpful.

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PR Type

Enhancement

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Description

• Remove UART3 configuration to prevent receiver confusion

• Update serial port count from 7 to 6

• Enable DMA support for DShot ESC protocol

• Set motor count to 7 for proper PWM configuration

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Diagram Walkthrough

flowchart LR
  A["UART3 Config"] -->|removed| B["6 Serial Ports"]
  C["DShot Protocol"] -->|enable DMA| D["USE_DSHOT_DMAR"]
  E["Motor Config"] -->|set count| F["TARGET_MOTOR_COUNT 7"]

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File Walkthrough

	Relevant files
Configuration changes	target.h Remove UART3, enable DShot DMA, configure motors                  src/main/target/NEXUSX/target.h Removed UART3 definition and pin configuration (PB10/PB11) Decreased SERIAL_PORT_COUNT from 7 to 6 Added USE_DSHOT_DMAR flag for DMA-accelerated DShot Added TARGET_MOTOR_COUNT set to 7 +5/-6

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[qodo-merge-pro]

PR Compliance Guide 🔍

Below is a summary of compliance checks for this PR:

Security Compliance
🟢	No security concerns identified No security vulnerabilities detected by AI analysis. Human verification advised for critical code.
Ticket Compliance
⚪	🎫 No ticket provided Create ticket/issue
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
⚪	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: No runtime logs: The changes are compile-time target configuration macros without any runtime action handling or logging, so there is no evidence of audit logging for critical actions in the added lines. Referred Code #define SERIAL_PORT_COUNT 6 #define DEFAULT_RX_TYPE RX_TYPE_SERIAL #define SERIALRX_PROVIDER SERIALRX_CRSF #define SERIALRX_UART SERIAL_PORT_USART5 #define SENSORS_SET (SENSOR_ACC|SENSOR_BARO) // *************** ADC ***************************** #define USE_ADC #define ADC_INSTANCE ADC1 #define ADC1_DMA_STREAM DMA2_Stream0 #define ADC_CHANNEL_1_PIN PC2 #define ADC_CHANNEL_2_PIN PC1 #define ADC_CHANNEL_3_PIN PC0 #define VBAT_ADC_CHANNEL ADC_CHN_3 // port labelled "EXT-V" //BEC ADC is ADC_CHN_2 //BUS ADC is ADC_CHN_1 ... (clipped 26 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: No error handling: The added macros (e.g., SERIAL_PORT_COUNT, USE_DSHOT_DMAR, TARGET_MOTOR_COUNT) introduce configuration changes without accompanying error handling or validation in this diff, making robustness unassessable from the provided changes. Referred Code #define SERIAL_PORT_COUNT 6 #define DEFAULT_RX_TYPE RX_TYPE_SERIAL #define SERIALRX_PROVIDER SERIALRX_CRSF #define SERIALRX_UART SERIAL_PORT_USART5 #define SENSORS_SET (SENSOR_ACC|SENSOR_BARO) // *************** ADC ***************************** #define USE_ADC #define ADC_INSTANCE ADC1 #define ADC1_DMA_STREAM DMA2_Stream0 #define ADC_CHANNEL_1_PIN PC2 #define ADC_CHANNEL_2_PIN PC1 #define ADC_CHANNEL_3_PIN PC0 #define VBAT_ADC_CHANNEL ADC_CHN_3 // port labelled "EXT-V" //BEC ADC is ADC_CHN_2 //BUS ADC is ADC_CHN_1 ... (clipped 26 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: No input validation: The changes are static build-time configuration and do not include any input handling or validation logic, so compliance with secure input validation cannot be verified from the new code. Referred Code #define SERIAL_PORT_COUNT 6 #define DEFAULT_RX_TYPE RX_TYPE_SERIAL #define SERIALRX_PROVIDER SERIALRX_CRSF #define SERIALRX_UART SERIAL_PORT_USART5 #define SENSORS_SET (SENSOR_ACC|SENSOR_BARO) // *************** ADC ***************************** #define USE_ADC #define ADC_INSTANCE ADC1 #define ADC1_DMA_STREAM DMA2_Stream0 #define ADC_CHANNEL_1_PIN PC2 #define ADC_CHANNEL_2_PIN PC1 #define ADC_CHANNEL_3_PIN PC0 #define VBAT_ADC_CHANNEL ADC_CHN_3 // port labelled "EXT-V" //BEC ADC is ADC_CHN_2 //BUS ADC is ADC_CHN_1 ... (clipped 26 lines) Learn more about managing compliance generic rules or creating your own custom rules
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⚪ - Requires Further Human Verification
🏷️ - Compliance label

[qodo-merge-pro]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
Possible issue	Add missing DShot DMA resources Add the required DSHOT_DMA_M_... macro definitions for each of the 7 motors to correctly configure and enable the DShot DMA feature.* src/main/target/NEXUSX/target.h [151-152] #define USE_DSHOT_DMAR #define TARGET_MOTOR_COUNT 7 +// NOTE: The following DMA resource definitions are placeholders and MUST be +// verified against the NEXUSX board's actual hardware pinout and timer/DMA mapping. +// Motor 1 +#define DSHOT_DMA_M1_TIMER TIM5 +#define DSHOT_DMA_M1_CHANNEL TIM_Channel_1 +#define DSHOT_DMA_M1_STREAM DMA1_Stream2 +// Motor 2 +#define DSHOT_DMA_M2_TIMER TIM5 +#define DSHOT_DMA_M2_CHANNEL TIM_Channel_2 +#define DSHOT_DMA_M2_STREAM DMA1_Stream4 +// Motor 3 +#define DSHOT_DMA_M3_TIMER TIM4 +#define DSHOT_DMA_M3_CHANNEL TIM_Channel_1 +#define DSHOT_DMA_M3_STREAM DMA1_Stream0 +// Motor 4 +#define DSHOT_DMA_M4_TIMER TIM4 +#define DSHOT_DMA_M4_CHANNEL TIM_Channel_2 +#define DSHOT_DMA_M4_STREAM DMA1_Stream3 +// Motor 5 +#define DSHOT_DMA_M5_TIMER TIM3 +#define DSHOT_DMA_M5_CHANNEL TIM_Channel_1 +#define DSHOT_DMA_M5_STREAM DMA1_Stream4 +// Motor 6 +#define DSHOT_DMA_M6_TIMER TIM3 +#define DSHOT_DMA_M6_CHANNEL TIM_Channel_2 +#define DSHOT_DMA_M6_STREAM DMA1_Stream5 +// Motor 7 +#define DSHOT_DMA_M7_TIMER TIM2 +#define DSHOT_DMA_M7_CHANNEL TIM_Channel_3 +#define DSHOT_DMA_M7_STREAM DMA1_Stream1 + Apply / Chat Suggestion importance[1-10]: 9 __ Why: The suggestion correctly identifies that enabling USE_DSHOT_DMAR without defining the corresponding DMA resources for each motor will result in a non-functional feature, which is a critical omission in the PR.	High
Learned best practice	✅ Keep serial count consistent Suggestion Impact: The commit adjusted SERIAL_PORT_COUNT from 6 to 7 in conjunction with UART3 being enabled, keeping the serial count consistent with active UARTs. code diff: +-#define USE_UART3 +-// port labelled "C" +-#define UART3_TX_PIN PB10 +-#define UART3_RX_PIN PB11 + #define USE_UART4 // port labelled "A" #define UART4_TX_PIN PA0 @@ -103,7 +108,7 @@ #define UART6_TX_PIN PC6 #define UART6_RX_PIN PC7 -#define SERIAL_PORT_COUNT 6 +#define SERIAL_PORT_COUNT 7 Verify that reducing SERIAL_PORT_COUNT matches all enabled UARTs after removing USE_UART3; update this count or UART enables to keep it consistent with the actual number of active serial ports. src/main/target/NEXUSX/target.h [106] +// Ensure this matches the number of enabled UARTs (e.g., USART1, USART2, USART4, USART5, USART6, USB VCP?) #define SERIAL_PORT_COUNT 6 [Suggestion processed] Suggestion importance[1-10]: 5 __ Why: Relevant best practice - Align mode/enum priorities and related configuration counts across modules to maintain a single source of truth.	Low
Update

[functionpointer]

Unfortunately this won't be acceptable for Vantac RF007 as it is missing the "B" Port, further reducing the number of available uarts.

Additionally, this target doesn't have a current sensor, potentially leading users to add an external one which will need a uart.

How much work would it be to fix the initialisation order instead?

[sensei-hacker]

Unfortunately this won't be acceptable for Vantac RF007 as it is missing the "B" Port, further reducing the number of available uarts.

That might be a different target, with different considerations.

How much work would it be to fix the initialisation order instead?

I have no idea. Feel free to look into it. 😁

[functionpointer]

I have managed to find the issue, and it turns out there is a solution already implemented. Just have to activate like so: #11127

[sensei-hacker]

Thanks @functionpointer
I reverted the removal of uart3.

That just leaves using DMAR and setting it to no more than 7 motors, as only 7 work for me.
(the other outputs CAN be servos)

[functionpointer]

I have investigated the 7 motor limitation, and it can be removed by reassigning timers like so: #11129

With that PR no TARGET_MOTOR_COUNT is required.