Full RTEMS port to the Milkymist One. Supports Milkymist SoC 1.0.x.

Includes drivers for:

Multi-standard video input (PAL/SECAM/NTSC)
Two DMX512 (RS485) ports
MIDI IN and MIDI OUT ports
VGA output
AC'97 audio
NOR flash
10/100 Ethernet
Memory card (experimental and incomplete)
USB host connectors (input devices only, using the softusb-input firmware)
RC5 infrared receiver
RS232 debug port

For more information: http://www.milkymist.org/

UART

Initialization:

set the CSR_UART_DIVISOR to the correct VALUE,
depending on the internal frequency of the LatticeMico32 softcore.

for the ML401 board, this value is calculated using this formula : clk_frequency/230400/16
clk_frequency  = 100000000 Hz
=> we must set CSR_UART_DIVISOR to 27

How to send a byte to uart :

void writechar(char c)
{
            CSR_UART_RXTX = c;
        while(!(irq_pending() & IRQ_UARTTX));
        irq_ack(IRQ_UARTTX);
}

How to receive a byte from uart :

char readchar()
{
    char c;
    while(!(irq_pending() & IRQ_UARTRX));
    irq_ack(IRQ_UARTRX);
    c = CSR_UART_RXTX;
    return c;
}