DbwNode does not forward correct Brake Command in specific firmware versions

Reviewing the CAN TX traffic from the DataSpeed ROS Node to the DataSpeed Brake Module, it was found for old firmware revisions, the commanded “percent” does not go from 0 - 100%. Instead, it goes from 0.15 to 50%.

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It seems the issue is related to the fwd flag:

  bool fwd_abs = firmware_.findModule(M_ABS).valid(); // Does the ABS braking module exist?
  bool fwd_bpe = firmware_.findPlatform(M_BPEC) >= FIRMWARE_CMDTYPE; // Minimum required BPEC firmware version
  bool fwd = !pedal_luts_; // Forward command type, or apply pedal LUTs locally
  fwd |= fwd_abs; // The local pedal LUTs are for the BPEC module, the ABS module requires forwarding
  fwd &= fwd_bpe; // Only modern BPEC firmware supports forwarding the command type

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I.e. Firmware 2.0.0 will set:

fwd_abs = 0

fwd_bpe = 0

fwd = !pedal_luts_ → 1

fwd |= fw_abs → 1

fwd &= fwd_bpe → 0

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    case dbw_mkz_msgs::BrakeCmd::CMD_PERCENT:
      if (fwd) {
        ptr->CMD_TYPE = dbw_mkz_msgs::BrakeCmd::CMD_PERCENT;
        ptr->PCMD = std::clamp<float>(msg->pedal_cmd * UINT16_MAX, 0, UINT16_MAX);
      } else {
        ptr->CMD_TYPE = dbw_mkz_msgs::BrakeCmd::CMD_PEDAL;
        ptr->PCMD = std::clamp<float>(brakePedalFromPercent(msg->pedal_cmd) * UINT16_MAX, 0, UINT16_MAX);
      }

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When commanding CMD_PERCENT, it uses the BrakeLUT Table due to fwd is set to 0

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