Toying with a Juicebox

Got a new Toy. It’s a Juicebox from Mattel, a kids video and mp3 player. Actually it’s a linux based and has Samsung S3C44B0 ARM CPU, 8MB Flash and 2MB Ram. Since it has JTAG Pinouts you can use it as a really cheap ARM Dev Board. You can’t get one for around $10 at ebay. You find a lot of good info here.

Made some LCD test stuff, a 3d starfield and a simple fire demo. This code runs directly on the hardware not on top of the build-in linux. You need a JTAG cable to download the code directly into the RAM.

I’m using openocd for this:

halt 
wait_halt 
poll 
load_binary lcd_3.bin 0x0c001000 
resume 0x0c001000

pic1 pic1

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Nokia 6100 LCD

Got my Nokia 6100 LCD working. Long story of failures. First try was a LCD with a Epson controller from ebay for 10 Euros. But somehow someone failed to solder the smd socket proberly and it went a way ;-) ( thx max ) .

Next try was a Epson based LCD including a header board from sparkfun . But this time i wasn’t able to run some demo code which was made for the LPC2138 on my LPC2148. I think the board was to fast to talk to the display. I wasn’t able set up SPI on the LPC2148 correct. Need more investigation on that topic.

So i gave up at this point and decided to go for a atmega16. I did a devel board for that which is losy based on this schematics. The boads uses simple parport icsp and has a serial line for debugging and sending data.

Finally i threw some code together using the init commands found in this project. Added support for receiving images via uart and wrote an little python client for sending images.

Future plans are to port the glcd lib to the epson based lcd.

pic1 pic2

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EFSL for the ARM LPC2148

Found a LPC2138 port of the Embedded Filesystems Library. Took this stuff and made this working on my LPC2148.

Now i can access an SD-Card attached to the LPC2148. Currently the FAT filesystem is supported. The sample pgramm includes an minimal serial line shell which supports file reading and directoy listings.

MMC/SD Card Filesystem Test (P:LPC2148 L:EFSL)
CARD init...spiInit for SSP/SPI1
Card is initialising.
CSD: 00 26 00 32 5F 59 83 C8 BE FB CF FF 92 40 40 D7
Drive Size is 1015808000 Bytes (1984000 Sectors)
Init done...
Press Command: d r a 
You pressed : d
Directory of 'root':
TEST01      ( 6 bytes )
TEST02      ( 6 bytes )
TEST03      ( 6 bytes )
TEST04      ( 6 bytes )
TEST05      ( 6 bytes )
TEST06      ( 6 bytes )
TEST09      ( 6 bytes )
TEST10      ( 6 bytes )
LOGDAT9 TXT ( 833 bytes )
DUMMY   LOG ( 2754 bytes )

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ARM LPC2148 and Linux

Just got my ARM LPC2148 Dev Board from Olimex

I put together a small overview how to get things working using a linux host system.

Toolchain

  • GNU Compiler Toolchain
  • Serial Programmer
  • Sample Code

  • Crt0
  • Linkerscript
  • Init Routine
  • Simple IO Test
  • SIO Debug Console
  • GNU Compiler Toolchain

    I use a standard arm GNU toolchain. Actuallay found this binary download from mikrocontroller.net. But also my GBA Toolchain worked and produced good binaries. So a Gentoo ARM Crossdev should to the work. Think that the LPC is not too picky about that.

    Serial Programmer

    I tried lpc21isp but it didn’t work for me. So i ended up using lpc2k_pgm. It has little gui and where you can setup all needed configs. I use iHex format to upload to the dev board, where i had best results using quite slow sio speed like 9600bps. You have to enable BSL on the LPC2148 for ICSP. On my LPC the switch is called ‘ICSP1′ which needs to be set into ON position.

    Crt0

    Nothing special about that. Took it from similar LPC based projects.Just setup stack sizes and default IRQ vectors. Worked out of the box.

    Linkerscript

    Tooks this from a other LPC project. The script specifies the memory layout of the target system and defines the sections for the binary output.

    Init Routine

    Code found in startup.c does the PLL init. The LPC2148 has 12 Mhz internal crystal but can run up to 60Mhz when setting the PLL. Also the default IRQ Handlers are defined here.

    Simple IO Test

    I used the on-board leds for a simple IO test.

    
    int main(void)
    {
        unsigned int i;
        Initialize();
        ConsoleInit(60000000 / (16 * BAUD_RATE));
        puts("Init done\n");
        IODIR0 |= 1 < < 10;          // P0.10 is an output
        IODIR0 |= 1 << 11;          // P0.10 is an output
        IOSET0 = 1 << 10;           //LED off
        IOSET0 = 1 << 11;           //LED off
    
        while (1) {
            for (i = 0; i < 1000000; i++);
            IOSET0 = 1 << 10;       //LED off
            IOCLR0 = 1 << 11;       //LED on
            puts("led1: off  led2: on\n");
            for (i = 0; i < 1000000; i++);
            IOCLR0 = 1 << 10;       //LED on
            IOSET0 = 1 << 11;       //LED off
            puts("led1: on   led2: off\n");
        }
    }
    

    SIO Debug Console

    Addes a little module that uses one of the two serial line for debugging output. I use the same serial port as for for the ICSP, so after the flashing lpc2k_gpm will display the output directly without any setup changes.

    pic1 pic2 pic3

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