v1.2.7

[board707]

New in v1.2.7:

• new SPWM chip added: SM16380sh
• limited brightness control for SPWM driver classes by shifting color bits up and down - see dmd_spwm_panel example.
• new color conversion method HSV -> color444
• hopefully make SPWM driver code more stable

The SPWM support (especially for FM6363 driver) is still far from release level, use with caution.

---

This discussion was created from the release v1.2.7.

[kingdo9]

I'll reply to this one keep this thread the latest updated.
I've made a new thread thats collated all other resources, also another update to that register extractor, I've got the FM6363C registers now also. Just 5 repeating throughout the frames.
hzeller/rpi-rgb-led-matrix#1866

[board707]

Brightness control in SPWM Driver code.

Version 1.2.7 introduced a method for a limited brightness control of sPWM panels:

uint8_t shiftColorBrightnessDown(uint8_t shift)

Why do we need a separate method for changing brightness on SPWM drivers? The reason is that the OE input, used in standard panels for brightness control, typically acts as synchronization source in SPWM drivers, making traditional brightness control impossible.
To understand how "shifting" brightness control works, let's look at the data loaded into the driver. For each pixel, we must load 16 bits of data, of which, however, only the 14 or 13 least significant bits are used to generate the image.
The library works with Color444 , meaning we only use 4 bits per color for each pixel.
We can place these bits in the most significant bits of the pixel, which will maximize the brightness. This corresponds to the zero parameter of the method. By shifting the bits to the right, we reduce the brightness without losing color depth. Increasing the shift parameter by 1 corresponds to a halving of the brightness.

The number of shift levels is limited by the processing algorithm and depends on the driver model; it varies from 4 to 8 on different drivers. If you set a method parameter that is significantly greater than the maximum shift, the brightness will be set to the minimum, and the returned value will contain the maximum possible shift for the driver.

[kingdo9]

@board707 I believe you have an FM6373 display?
Alternative method if you need for this display, with it being gain, may be able to get a brighter display?

On FM6373 config

	uint16_t fm6373_conf[] = {
		0x021f, 0x033f, 0x0402, 0x0507, 0x0603, 0x0720, 0x0820, 0x0900, 0x0a00, 0x0b00,
		0x0c01, 0x0d01, 0x0e04, 0x0f01, 0x10c2, 0x1121, 0x1201, 0x17f0, 0x181f, 0x1900,
		0x1a1f, 0x1b10, 0x1cc1, 0x1d0a, 0x1e42, 0x1f04, 0x2008, 0x2101, 0x221c};

0x1cc1 index [28]
This is Gain if you change this value, doesn't change the actual color values.

22.05% - 1c[2a] - Lowest Nova lets me get down to.
102.96% - 1c[c1] - Default value.
199% - 1c[ff] - Maximum Nova lets me get to.

This document might have some other details for you., near the bottom has more details.
Group 29 (index 28) – current gain.

FM6373_Register_Info.md

[board707]

@kingdo9
Thank you so much. I've been wanting to figure out these settings for a while, but there wasn't enough information.
I'll definitely give it a try.

[board707]

The library Wiki updated to be consistent to v1.2.7 code.