example-21.txt

来自「DSP TMS320 LF2407 or 243 经典 例程, from TI」· 文本 代码 · 共 31 行

Example 21 : LED 

  

Hardware- Environment : 

This example runs on TI's evaluation board EVM TMS320LF2407 with additional glue hardware connected to the external board connectors P1 to P4. In this example we use the general purpose IO's Port E0..E7. Each Pin of Port E is used as output, connected with a resistor R1 (1,5k) to the basis of an npn-general purpose transistor. The emitter of this npn is connected to ground, the collector to the cathode of a LED. The anode of the LED is connected with an resistor R2 (220 Ohm) to +3.3V 

CAUTION !!!  DO NOT wire any of the DSP I/O-pins, available through P1 to P4, directly to +5V ! This will damage the DSP definitely because this DSP is a low-voltage type (3.3V). Pin 1 and 2 of the connectors P1 to P4 carry +5V !!!. 

Aim: 

The program generates a 'running light' on the 8 LED's connected to GPIO-E0...E7 

Files: 

Generate a new project inside Code Composer, the Go-DSP integrated design environment. The project consists of the following files, all files can be downloaded ( see zip-file )

 LED.c            -- C-source code for this example 

 vectors.asm   -- jump vector table for Interrupt Service Routines 

 regs2407.h      -- pointer definitions to memory mapped  perihperals 

 LED.cmd -- memory map definition file for the linker 

 init2407.gel       -- Code Composer Setup file ( GO-DSP extension language ) 

 rts2xx.lib          -- runtime library file (part of TI's compiler/assembler)   

    Download (all files zipped):   Example 21