I am currently trying to interface a MAX7219 LED driver with a Bus Pirate 3.6 (Firmware v5.10 (r559) Bootloader v4.4).
Here is the datesheet :www.componentschip.com/.../MAX7219.html
I have the following circuit breadboarded (along with some decoupling caps on the power rail):
Circuit Diagram
I have set up SPI mode as such: Set speed: 1. 30KHz 2. 125KHz 3. 250KHz 4. 1MHz
(1)>4 Clock polarity: 1. Idle low *default 2. Idle high
(1)>1 Output clock edge: 1. Idle to active 2. Active to idle *default
(2)>1 Input sample phase: 1. Middle *default 2. End
(1)>1 CS: 1. CS 2. /CS *default
(2)>2 Select output type: 1. Open drain (H=Hi-Z, L=GND) 2. Normal (H=3.3V, L=GND)
(1)>2 Ready
Putting the MAX7219 into test mode and turning it off using [0xFF,0xFF] and [0xFF, 0x00] respectively turns all the LEDs on and off as expected. Restarting everything, I then run the following commands to disable character decoding (to use the MAX as a simple LED array drive), set maximum brightness, enable all columns, and finally enable the display:
[0x09,0x00] [0x0A,0xFF] [0x0B,0x07] [0x0C,0x01]
Finally, sending the following eight commands to enable all LEDs akin to what test mode would do does not have any effect, and no LEDs light up;
[0x01, 0xFF] [0x02, 0xFF] [0x03, 0xFF] [0x04, 0xFF] [0x05, 0xFF] [0x06, 0xFF] [0x07, 0xFF] [0x08, 0xFF]
At any point, I can set or reset test mode and it works as expect, so I'm convinced that SPI communication integrity is not the issue here.
I have tried this with both 5V and 3V3 levels for VCC, with the same results. Any ideas what I may be doing wrong here?
What does this have to do with Keil??
"The Keil Discussion Forum is an open forum where you may post questions and comments about Keil products."http://www.keil.com/forum/
Yes. Don't you just hate it when people do that. Even worse when they then try to sweeten it D:<
http://www.keil.com/forum/15732/