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tinygo-org / drivers

TinyGo drivers for sensors, displays, wireless adaptors, and other devices that use I2C, SPI, GPIO, ADC, and UART interfaces.
https://tinygo.org
BSD 3-Clause "New" or "Revised" License
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[HUB75]Leds do not light up as expected #691

Open ehime-iyokan opened 4 months ago

ehime-iyokan commented 4 months ago

I wrote program using hub75 package and raspberry pi pico. but, it didn't light up. So I have tried to fix hub75. As a result. It light up as expected. And Environmental information is here. -> https://github.com/ehime-iyokan/tinygo_hub75_sample

picture1

First, I added a time.sleep(1 * time.Microsecond) after latch-High. By doing so, the light came on. However, I don't know why, so if you know, please let me know. Moreover, the red lights are on in different places.

picture2

Second, I fixed buffering of red data. I guess it has to do left-shift first. d.buffer[c][offsetR] = d.buffer[c][offsetR] &^ 1 << bitSelect -> d.buffer[c][offsetR] &^= 1 << bitSelect

picture3

ehime-iyokan commented 4 months ago

I added a time.sleep(1 * time.Microsecond) after latch-High. By doing so, the light came on. However, I don't know why If I figured out why it worked correctly, I'll create a pull request.

sago35 commented 4 months ago

@ehime-iyokan The GPIO of the RP2040 might be too fast. Without adding time.Sleep(), the pulse width is 110ns, which might be too short. With time.Sleep(), it is around 5us.

I think the fix you are considering is necessary.

with time.Sleep(1 * time.Microsecond) : 5.046us

image

without time.Sleep(1 * time.Microsecond) : 110ns

image

sago35 commented 4 months ago

Including other parts as well, it is better to use delay.Sleep() for microsecond sleeps. I think it would be good if you could create a Pull Request with that change.

https://github.com/tinygo-org/drivers/blob/v0.28.0/delay/sleep.go

with delay.Sleep(1 * time.Microsecond) : 1.16us

image

ehime-iyokan commented 3 weeks ago

I created pullrequest. => (https://github.com/tinygo-org/drivers/pull/722)

Second, I fixed buffering of red data.
I guess it has to do left-shift first.
d.buffer[c][offsetR] = d.buffer[c][offsetR] &^ 1 << bitSelect
-> d.buffer[c][offsetR] &^= 1 << bitSelect

(https://github.com/tinygo-org/drivers/issues/691#issue-2386396643)

ehime-iyokan commented 3 weeks ago

Thank you for providing the information. @sago35 For now, I've decided to use a microcontroller board other than the RP2040. Next time I use the RP2040, I’ll consider creating a pull request.