Addressing multiple PORTs using one Variable

[HenrikOlsson]

Are you displaying the same "information" on all 5 strings or calculating the "content" for each string on the fly as you go about updating them?
Reason I ask is that 5 strings times 28 LEDs times 3 bytes per LED equals 420 bytes and the 16F690 only has 256 bytes of RAM.

[flotulopex]

It is (going to be) a four digits 7 "segments" (each segment is made up of four NeoPixels >> 4x7= 28 NeoPixels per string) wall clock.

The fifth segment is made of 2 or 4 four (not decided yet) NeoPixels and will serve as seconds separator/indicator.

Yes, each string will be uptated specifically, if I can say so.

By now, it all fits in my 16F690 nicely because I address the strings only once at the time or 1x28x3 bytes in total.

[richard]

Can all the outputs be on the same port, preferably sequential?

[flotulopex]

Can all the outputs be on the same port, preferably sequential?

As Henrik pointed, I'm somehow limited in the number of bytes I can use to address the NeoPixel strings.

Because of the very narrow timings, I cannot use routines to address the strings repeatetely with GOTOs/FOR-NEXTs/GOSUBs and so on. For this reason, I have to write code to address 24 bits for one Pixel in a row and only here, I can repeat the routine with one of the previous mentionned commands. This to say there is not only a timing issue but it is also about code length or space in the PIC.

Having this limitations in mind, I started my project addressing one string at the time and I've got plenty of time to display a minute based clock. Since all strings use the same common code and therefore the same variables, I can only differentiate them using different ports.

So if you mean to have only one NeoPixel string made of (4 digits x 7 segments x 4 Pixels [or LEDs] x 3 bytes per Pixel) + (4 Pixels x 3 bytes per Pixel) = 348 bytes, I can't address them in an array, as far as I understand it.

But what do you have in mind, please?

[Ioannis]

There is an easier protocol for addressable LEDs. The APA102 that is not strict on timing.

https://learn.sparkfun.com/tutorials...okup-guide/all

Ioannis

[richard]

Having this limitations in mind, I started my project addressing one string at the time and I've got plenty of time to display a minute based clock. Since all strings use the same common code and therefore the same variables, I can only differentiate them using different ports.

a 16f690 has 3 ports A,B and C by different ports do you mean different pins ?


Can all the outputs be on the same port, preferably sequential?
ie RC0:4 OR RC3:7 or similar

[flotulopex]

Yes, ports will be in a sequential order.

I'll be using ports:

• Seconds: PORTC.3
• Minutes Units: PORTC.4
• Minutes Thenths: PORTC.5
• Hours Units: PORTC.6
• Hours Tenths: PORTC.7

16F690 has:
PORTA.0..5
PORTB.4..7
PORTC.0..7