So you know that first number in the blade configuration?
Do you know what it's for?
It's the Blade ID.
When ProffieOS starts, it measures the resistance between the Blade ID pin (which is usually the same as the neopixel data pin for the first blade) and GND. It then finds the entry in the blades table with the closest first number, and then it uses that entry until the next time it scans for a blade. This may be at power on, or triggered by Blade Detect. An example of a BladeConfig with multiple, different resistor value blades is shown here:
BladeConfig blades[] = {
{ 5000,
WS281XBladePtr<132, bladePin, Color8::GRB, PowerPINS<bladePowerPin2, bladePowerPin3> >(),
CONFIGARRAY(blade1_in) },
{ 10000,
WS281XBladePtr<128, bladePin, Color8::GRB, PowerPINS<bladePowerPin2, bladePowerPin3> >(),
CONFIGARRAY(blade2_in) },
{ NO_BLADE,
WS281XBladePtr<144, bladePin, Color8::GRB, PowerPINS<bladePowerPin2, bladePowerPin3> >(),
CONFIGARRAY(no_blade) },
};
So how do you use this?
Well, the idea is that if you have multiple blades, you can place a resistor between the data pin and GND, and ProffieOS can use that resistor to identify which blade is connected. In the simplest possible case, this could be used to support WS281X blades of different lengths, but it's also possible to support entirely different types of blades, assuming your blade connector has enough pins.
Note that the Blade ID resistor is different from the in-line resistor normally used for WS281X blades. The resistors are also different sizes. The in-line resistor should be 150-470 ohms, but the Blade ID resistor should be somewhere in the 2k to 100k range. Any lower may interfere with the blade data.
The V1 electronics is still one of the best pictures for showing how this can work: https://fredrik.hubbe.net/lightsaber/electronics.html
Unfortunately, it turns out that Proffieboard V1.5 and V2.2s are unable to do Blade ID in the same way as TeensySabers do, because there is no way to enable a pullup/pulldown resistor while doing an analog read from the pin. Several options can be defined to help with this as of ProffieOS 3.x.
NOTE - These are not needed for a Proffieboard V3. V3 already has a Bridged Pullup internally.
The first BLADE_ID_CLASS option is the default on Proffieboards V1.5 and V2.2s. Therefore it does not need to be specified in the config file, but here is what it is and what it does:
#define BLADE_ID_CLASS SnapshotBladeID<bladeIdentifyPin>
The default blade ID class SnapshotBladeID charges up the internal sampling capacitor, then connects the sampling capacitor to the Blade ID pin for a very short time, and then does the analog-to-digital conversion. This should give consistent values for the same blade, but unfortunately, the values will not reflect the actual value of the Blade ID resistor in the blade. The blades array has to be configured with these measured values instead. Measured values can be found by using Serial Monitor in Arduino, and entering scanid while the blade is off. This will report "BLADE ID: N" where N is the measured value.
Alternatively, an external pull-up resistor can be used. This resistor should be in the 20k to 50k range and placed between the blade pin and 3.3v. Then you add this to the config file:
#define BLADE_ID_CLASS ExternalPullupBladeID<bladeIdentifyPin, 22000>
(Replace 22000 with the value of your pullup resistor.) With this workaround, Blade ID should return values that are close to the Blade ID resistor values, which will make configuration easier.
Another option is to bridge the blade pin with another pin and use that pull-up resistor. This is the default method on a V3 board as it is built-in already, so it does not to be specified.
On a Proffieboard V2.2, the ID pin is right next to the TX pin. If you bridge those two together, and put this is your config file:
#define BLADE_ID_CLASS BridgedPullupBladeID<bladeIdentifyPin, 9>
(9 is the pin number for the TX pin) With this, Blade ID should return the actual value of the Blade ID Resistor. Use this value in the blade definition.
Another quirk of Blade ID is that unpowered neopixels throws it off. When the neopixels are powered, the inputs are high impedance, which doesn't affect the Blade ID, but when unpowered, they leech power from the data line, which throws off the Blade ID value. The solution is to turn the power on while we're doing Blade ID by using the ENABLE_POWER_FOR_ID define. If your blade is hooked up to the LED2 and LED3 pads, it would look like this:
#define ENABLE_POWER_FOR_ID PowerPINS<bladePowerPin2,bladePowerPin3>
IMPORTANT NOTE - BladeID requires a direct, uninterrupted connection from the board's data pin to the main blade (usually the center pin on the hilt-side of the main blade PCB). Therefore using SubBlades with neopixel accents, crystal chamber, or NPXL LED PCBs in series with the main blade won't work. They can be their own SubBlade chain on a data pin other than data1, but only data1 can use BladeID.
Here's an example template of a config file formatted to use Blade ID:
// This is a simplified config file template set up for Blade ID.
#ifdef CONFIG_TOP
#define SHARED_POWER_PINS
// #define BLADE_DETECT_PIN blade4Pin
#define ENABLE_POWER_FOR_ID PowerPINS<bladePowerPin2, bladePowerPin3>
// #define BLADE_ID_CLASS ExternalPullupBladeID<bladeIdentifyPin, 33000> // value of resistor used
// #define BLADE_ID_CLASS BridgedPullupBladeID<bladeIdentifyPin, 9> // TX pad for example
/* This will make it use the speed-of-charging-a-capacitor method of blade ID which sometimes works without resistors.
Blade ID can detect if a blade is connected or not, but it won't actually reach the NO_BLADE value,
so I would recommend using something like 200000 instead of NO_BLADE. */
#define BLADE_ID_CLASS SnapshotBladeID<bladeIdentifyPin>
/* Millis is Blade ID scan interval. If the blade ID comes out the same as before, it will do nothing.
If it comes out different, it will do FindBladeAgain(), which will basically initialize the saber from
scratch and load the right settings for the new id().
It will only work with neopixel blades, and requires SHARED_POWER_PINS to work. */
#define BLADE_ID_SCAN_MILLIS 1000
// How many Blade ID scans to average
#define BLADE_ID_TIMES 15
// other defines go here
#endif
#ifdef CONFIG_PROP
#include "../props/PROP_FILE_OF_CHOICE_GOES_HERE.h"
#endif
#ifdef CONFIG_PRESETS
Preset blade_1 [] = {
{ "font", "tracks/track",
StylePtr<Red>(), "preset name"},
};
//---------------------------------------------------------------
Preset blade_2 [] = {
{ "font", "tracks/track",
StylePtr<Green>(), "preset name"},
};
//---------------------------------------------------------------
Preset no_blade[] = {
{ "font", "tracks/track",
StylePtr<Blue>(), "preset name"},
};
BladesConfig blades[] = {
{ 10000,
WS281XBladePtr<123, bladePin, Color8::GRB, PowerPINS<bladePowerPin2, bladePowerPin3> >(),
CONFIGARRAY(blade_1), "blade_1_Save" },
{ 33000,
WS281XBladePtr<144, bladePin, Color8::GRB, PowerPINS<bladePowerPin2, bladePowerPin3> >(),
CONFIGARRAY(blade_2), "blade_2_Save" },
{ 200000,
WS281XBladePtr<1, bladePin, Color8::GRB, PowerPINS<bladePowerPin2, bladePowerPin3> >(),
CONFIGARRAY(no_blade), "no_blade_Save" }
};
#endif
#ifdef CONFIG_BUTTONS
Button PowerButton(BUTTON_POWER, powerButtonPin, "pow");
Button AuxButton(BUTTON_AUX, auxPin, "aux");
#endif
As of ProffieOS7, a new method of detecting different "blades" by using Blade ID is available.
See Blade ID constant monitoring.