Author Topic: interfacing display to spi evk1100  (Read 5368 times)

Offline sam_newbie

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interfacing display to spi evk1100
« on: May 18, 2011, 12:18:46 PM »
hello folks ,
 
This is my first post in this forum and very much new to avr programming .. I need few clarification.. hope I get some help from you guys ..

I am trying to interface a LCD to my avr 32 evk1100 board through SPI port.. I am confused whether I shall use the SPI SPARE port(near the reset button) or the SPI port available near the power supply .. does it have different functionalities ??

and has anyone configured the SPI spare port before?

Offline mark

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Re: interfacing display to spi evk1100
« Reply #1 on: May 18, 2011, 02:23:24 PM »
Hi

The EVK1100 has an AVR32 with 2 SPI interfaces (SPI0 and SPI1).

On the board SPI1 is used to interface to the on-board LCD (using CS2), the on-board ATMLE Data Flash (CS0) and the SD card socket (CS1).

SPI0 is not used on the board and is connected to J6 (the spare SPI connector), whereby CS0 from SPI0 is available on the connector.

Both SPIs are effectively identical. SPI0 is addressed via the SPI0 register and the SPI1 via the SPI1 registers but this is a programming detail.

If using the LCD on the board it can be controlled via SPI1. If adding a different/external LCD it is possible to add it to SPI1 (using a different chip select line) or to SPI0. I would recommend connecting to SPI0 (J6) for three reasons:
1) The connector is more practical for connection.
2) Using a different SPI to the on-board parts means that the SW doesn't have to consider that it may be sharing the port with other activity.
3) Keeping the two SPI interfaces serarate also means that there is less loading on the second SPI interface, meaning that the signals will be a bit cleaner at longer distances.

Regards

Mark

Offline sam_newbie

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Re: interfacing display to spi evk1100
« Reply #2 on: May 18, 2011, 07:55:36 PM »
thanx alot mark !!!  ;D

Offline mhoneywill

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Re: interfacing display to spi evk1100
« Reply #3 on: May 19, 2011, 01:38:14 PM »
Hi,

Out of interest what type of screen are you trying to interface via SPI? do you have a part number

Cheers

Martin