Seven Segment Display

[mlipham]

Hey,

I have the EK2500 eval kit from Synapse. I am migrating from the eval board to a prototype version. Basically, our prototype will have two large 7-segment displays. I am interested in how Syanpse got the two-digit display to work on the eval board. I am tracing the code back to a script called setSegments(segments). This is actually a built-in SNAPpy module in the RF modules. Does anyone know how I can get access to this? I would like to see the code in this module. From what I have read, the two-digit display on the eval board is controlled by only using two IO pins. This would be great if I could get our prototype to work this way.

Any help greatly appreciated,

Mark

[kbanks]

We do not provide source code or hardware schematics for our products (we made an exception for the SN171 Proto Board because there is so little hardware on it).

Still, I agree it would be great if your (larger) seven-segment displays worked the same as the ones on the SN163 and SN111 boards. Here is how that external display hardware "looks" to the RFE.

Synapse "demo board" LED displays are controlled by 4 logical signals, multiplexed onto 2 physical pins (we have some very clever hardware designers).

CLK and ON/OFF control are both on RFE GPIO 13.
GPIO 13 low turns the display off, GPIO 13 high turns it on.
(You will sometimes see us writing GPIO 13 low before going to sleep in some of our example scripts, now you know why).

In addition, a low-going pulse (--_--) on this pin "clocks" a data bit into the external hardware.

DATA and DIGIT SELECT are on RFE GPIO 14.
GPIO_14 low selects the right-hand digit, high selects the left-hand digit.
(better check me on this).
Individual data bits are clocked in most significant bit first, with a low (0) corresponding to a LIT segment. (The setSegments() built-in normally takes care of inverting the requested values for you).

So, if you will connect external hardware that conforms to this hardware interface, you can continue to use the setSegments() built-in to drive your custom display.

If your script NEVER calls setSegments(), then the core firmware leaves these pins alone. This means you can experiment with these pins using standard setPinDir()/writePin() calls, in order to verify your understanding of the existing demo hardware.

Any help beyond what I just gave you (in this post) is probably within the scope of Custom Solutions work.

[kbanks]

If you put your example code (I assume it is some form of PIC Basic) inside of [ c o d e ] ... [ / c o d e ] (but without the extra spaces, others will be able to read it easier.

Also, can you tell us a little about how the RF Engine then interfaced with the easypic3?

[bcuming]

I need to add a 7 segment LED display too. Your comment "So, if you will connect external hardware that conforms to this hardware interface, you can continue to use the setSegments() built-in to drive your custom display" Can you give me an example which 7 segment product/part number will work?
Thanks

[kbanks]

We do not provide source code or hardware schematics for our products...

So, re-read my functional description and then look at the 74AC299MTR shift register and the LDD_E302NI dual digit seven segment display.

If you need more detail than that, you will have to contact the Custom Solutions Group.

Also, if you look in the example scripts that come with version 2.4, there is now a SevenSegment.py example script (for platforms that do not support the setSegments() built-in.) This script should supplement the descriptions I gave in this thread.