HT1632 with LED matrix display

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi all,
I've been following this thread on a similar 16x24 display as a guide to wiring up my HT1632-based 8x32 LED matrix display.
Their datasheet vs. my datasheet

Post #8 on that thread lists some code to turn all the LEDs on, then off for the 16x24 board. Running it after a copy-paste makes the first 24 columns light up as they should, but the last 8 columns are skipped before it starts turning off [see attached image of just before it starts turning off]

I can't find what in the code is causing this. Bit shifting is new to me, and since I'd imagine the problem is in the loop() function, I don't think I'll be able to find it quickly. From my understanding, the first loop is from 0 to 95, the nested one over 8,12,14,15. That's great, but I don't see how it relates to the datasheet for the 16x24 board, much less what I should change for it to work on the 8x32 board.

from imageuploading.net

2

You have to change the HT1632_CMD_COMS11 to HT1632_CMD_COMS10 for 0832 display

void setup ()  // flow chart from page 17 of datasheet
{
  pinMode(ht1632_cs, OUTPUT);
  digitalWrite(ht1632_cs, HIGH);       /* unselect (active low) */
  pinMode(ht1632_wrclk, OUTPUT);
  pinMode(ht1632_data, OUTPUT);
  ht1632_sendcmd(HT1632_CMD_SYSDIS);  // Disable system
  ht1632_sendcmd(HT1632_CMD_COMS10);  // 8*32, PMOS drivers
  ht1632_sendcmd(HT1632_CMD_MSTMD);       /* Master Mode */
  ht1632_sendcmd(HT1632_CMD_SYSON);       /* System on */
  ht1632_sendcmd(HT1632_CMD_LEDON);       /* LEDs on */
  for (byte i=0; i<128; i++)
    ht1632_senddata(i, 0);  // clear the display!
  delay(LONGDELAY);
}
3

Thanks Bill.
I think there must be something else going on. I made the change, but now it seems to set the LEDs on for 1.5 times then off for 1.5 the length of the board. Ideas?
See videohttp://www.youtube.com/watch?v=99AHsLYdhj0

4

for the two loop change from 96 to 64

5

Awesome!

I got me one of the 8x32 displays the other day and it's working thanks to this thread (and the main one about the other shaped ones).

Thanks!