Category: ARM

Found a LPC2138 port of the [Embedded Filesystems Library](http://www.efsl.be/). 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 )

[download source](http://optixx.org/download/efsl.tar.gz)

Just got my ARM LPC2148 Dev Board from [Olimex](http://www.olimex.com)

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

Toolchain

Sample Code

GNU Compiler Toolchain

I use a standard arm GNU toolchain. Actuallay found [this binary](http://www.mikrocontroller.net/en/arm-gcc) 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](http://guest.engelschall.com/~martin/lpc21xx/isp/) but it didn’t work for me. So i ended up using [lpc2k_pgm](http://www.pjrc.com/arm/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.


[download source](http://optixx.org/download/blink2148.tar.gz)