Timeline for Multiple micro controllers to control LED matrix
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Aug 15, 2013 at 7:00 | vote | accept | Nick | ||
| Apr 6, 2013 at 3:06 | comment | added | user3624 | @angelatlarge If the LED's are in a matrix then you will want to "overdrive" the LEDs. Otherwise they appear too dim. The exact drive current will depend on the LED, but 30 to 90 mA is common. Carefully read the LED datasheets and it will give you an idea about what is acceptable (but usually it is just a starting point). | |
| Apr 6, 2013 at 2:55 | comment | added | angelatlarge | I was thinking 70 leds x 10mA/LED (lowballing!) / 4 PICs = 175mA / PIC... | |
| Apr 6, 2013 at 2:49 | comment | added | user3624 | @angelatlarge You need additional driving circuitry with PIC's and FPGA's. Although I should mention that there are dedicated LED driver chips out there with built in shift registers! If my options are to bit-bang a 2-8 bit wide SPI vs. use a 1-bit wide SPI controller w/DMA then I'll choose the DMA option every time. ti.com/lit/ds/symlink/tlc5928.pdf | |
| Apr 6, 2013 at 2:41 | comment | added | angelatlarge | Agreed on multi-CPU, but two quibbles/questions: a) with multi-PICs, I thought OP was hoping to avoid additional driving circuitry, whereas with FPGAs you'll definitely need LED drivers. b) depending on your needs, bit-banging can be more effective than built-in SPI (such as when you want to bit-bang parallel SPI outputs) | |
| Apr 6, 2013 at 2:31 | history | answered | user3624 | CC BY-SA 3.0 |