scih8.c

avr上的RTOS

            if (brr > 0xff) {
                cks = 2;
                brr = ((NutGetCpuClock() / (64UL * 8UL)) / *lvp) - 1;
                if (brr > 0xff) {
                    cks = 3;
                    brr = ((NutGetCpuClock() / (64UL * 32UL)) / *lvp) - 1;
                }
            }
        }
        sci->SMR.BIT.CKS = cks;
        sci->BRR = (u_char) brr;
        dcb->dcb_baudSelect = brr;
        NutDelay(2);            /* wait for a while */
        SciH8Enable(devnum);
        break;

    case UART_GETSPEED:
        switch (sci->SMR.BIT.CKS) {
        case 0:
            *lvp = NutGetCpuClock() / ((64UL / 2UL) * (u_long) (sci->BRR + 1));
            break;
        case 1:
            *lvp = NutGetCpuClock() / ((64UL * 2UL) * (u_long) (sci->BRR + 1));
            break;
        case 2:
            *lvp = NutGetCpuClock() / ((64UL * 8UL) * (u_long) (sci->BRR + 1));
            break;
        case 3:
            *lvp = NutGetCpuClock() / ((64UL * 32UL) * (u_long) (sci->BRR + 1));
            break;
        }
        break;

    case UART_SETDATABITS:
        SciH8Disable(devnum);
        switch (bv) {
        case 8:                /* 8 data bits */
            sci->SMR.BIT.CHR = 0;
            break;
        case 7:                /* 7 data bits */
            sci->SMR.BIT.CHR = 1;
            break;
        default:
            rc = -1;
        }
        SciH8Enable(devnum);
        break;

    case UART_GETDATABITS:
        switch (sci->SMR.BIT.CHR) {
        case 0:                /* 8 data bits */
            *lvp = 8;
            break;
        case 1:                /* 7 data bits */
            *lvp = 7;
            break;
        }
        break;

    case UART_SETPARITY:
        SciH8Disable(devnum);
        switch (bv) {
        case 'n':              /* none */
            sci->SMR.BIT.PE = 0;
            break;
        case 'e':              /* even */
            sci->SMR.BIT.PE = 1;
            sci->SMR.BIT.OE = 0;
            break;
        case 'o':              /* odd */
            sci->SMR.BIT.PE = 1;
            sci->SMR.BIT.OE = 1;
            break;
        default:
            rc = -1;
        }
        SciH8Enable(devnum);
        break;

    case UART_GETPARITY:
        if (sci->SMR.BIT.PE == 0) {     /* none */
            bv = 'n';
        } else if (sci->SMR.BIT.OE == 0) {      /* even */
            bv = 'e';
        } else {                /* odd */
            bv = 'o';
        }
        break;

    case UART_SETSTOPBITS:
        SciH8Disable(devnum);
        switch (bv) {
        case 1:                /* 1 stop bit */
            sci->SMR.BIT.STOP = 0;
            break;
        case 2:                /* 2 stop bits */
            sci->SMR.BIT.STOP = 1;
            break;
        default:
            rc = -1;
        }
        SciH8Enable(devnum);
        break;

    case UART_GETSTOPBITS:
        switch (sci->SMR.BIT.STOP) {
        case 0:                /* 1 stop bit */
            *lvp = 1;
            break;
        case 1:                /* 2 stop bits */
            *lvp = 2;
            break;
        }
        break;

    case UART_GETSTATUS:
        SciH8GetStatus(dev, lvp);
        break;
    case UART_SETSTATUS:
        rc = -1;
        break;

    case UART_SETREADTIMEOUT:
        dcb->dcb_rtimeout = lv;
        break;
    case UART_GETREADTIMEOUT:
        *lvp = dcb->dcb_rtimeout;
        break;

    case UART_SETWRITETIMEOUT:
        dcb->dcb_wtimeout = lv;
        break;
    case UART_GETWRITETIMEOUT:
        *lvp = dcb->dcb_wtimeout;
        break;

    case UART_SETLOCALECHO:
        if (bv)
            dcb->dcb_modeflags |= UART_MF_LOCALECHO;
        else
            dcb->dcb_modeflags &= ~UART_MF_LOCALECHO;
        break;
    case UART_GETLOCALECHO:
        if (dcb->dcb_modeflags & UART_MF_LOCALECHO)
            *lvp = 1;
        else
            *lvp = 0;
        break;

    case UART_SETFLOWCONTROL:
        if (bv)
            dcb->dcb_modeflags |= UART_MF_LOCALECHO;
        else
            dcb->dcb_modeflags &= ~UART_MF_LOCALECHO;
        break;
    case UART_GETFLOWCONTROL:
        break;

    case UART_SETCOOKEDMODE:
        if (bv)
            dcb->dcb_modeflags |= UART_MF_COOKEDMODE;
        else
            dcb->dcb_modeflags &= ~UART_MF_COOKEDMODE;
        break;
    case UART_GETCOOKEDMODE:
        if (dcb->dcb_modeflags & UART_MF_COOKEDMODE)
            *lvp = 1;
        else
            *lvp = 0;
        break;

    default:
        rc = -1;
        break;
    }
    return rc;
}

/*!
 * \brief Initialize on chip uart device.
 *
 * Prepares the device for subsequent reading or writing.
 * Enables SCI transmitter and receiver interrupts.
 *
 * \param dev  Identifies the device to initialize.
 *
 * \return 0 on success, -1 otherwise.
 */
int SciH8Init(NUTDEVICE * dev)
{
    IFSTREAM *ifs;
    UARTDCB *dcb;
    u_long baudrate = 9600;
    volatile struct st_sci *sci = GET_SCI(dev->dev_base);

    /*
     * We only support character devices for on-chip SCIs.
     */
    if (dev->dev_type != IFTYP_STREAM || dev->dev_irq != 0 || (dev->dev_base != 0 && dev->dev_base != 1 && dev->dev_base != 2))
        return -1;

    /*
     * Initialize interface control block.
     */
    ifs = dev->dev_icb;
    memset(ifs, 0, sizeof(IFSTREAM));
    ifs->if_input = SciH8Input;
    ifs->if_output = SciH8Output;
    ifs->if_flush = SciH8Flush;

    /*
     * Initialize driver control block.
     */
    dcb = dev->dev_dcb;
    memset(dcb, 0, sizeof(UARTDCB));
/*     dcb->dcb_baudSelect = 7; */
    dcb->dcb_modeflags = UART_MF_NOBUFFER;

    /*
     * Register interrupt handler.
     */
    if (dev->dev_base == 2) {
        if (NutRegisterIrqHandler(&sig_RXI2, RxComplete, dev))
            return -1;
        if (NutRegisterIrqHandler(&sig_TXI2, TxComplete, dev))
            return -1;
    } else if (dev->dev_base == 1) {
        if (NutRegisterIrqHandler(&sig_RXI1, RxComplete, dev))
            return -1;
        if (NutRegisterIrqHandler(&sig_TXI1, TxComplete, dev))
            return -1;
    } else if (dev->dev_base == 0) {
        if (NutRegisterIrqHandler(&sig_RXI0, RxComplete, dev))
            return -1;
        if (NutRegisterIrqHandler(&sig_TXI0, TxComplete, dev))
            return -1;
    }
    sci->SCR.BYTE = 0;
    /* Set for Async, data bits, parity, stop bit and an undivided clock. */
    sci->SMR.BYTE = DATABITS_8 | NOPARITY | STOP1BIT | NODIVIDE;
    /* Clear relevant status bits. */
    sci->SSR.BYTE = ~(PER | FER | ORER | RDRF);
    sci->SCR.BYTE = (RXI_ENABLE | RX_ENABLE | TX_ENABLE);

    /*
     * Set baudrate and handshake default. This will also
     * enable the UART functions.
     */
    SciH8IOCtl(dev, UART_SETSPEED, &baudrate);

    return 0;
}

/*!
 * \brief Read from device.
 */
int SciH8Read(NUTFILE * fp, void *buffer, int size)
{
    int rc;
    NUTDEVICE *dev;
    IFSTREAM *ifs;
    UARTDCB *dcb;
    u_char elmode;
    u_char ch;
    u_char *cp = buffer;

    dev = fp->nf_dev;
    ifs = (IFSTREAM *) dev->dev_icb;
    dcb = dev->dev_dcb;

    if (dcb->dcb_modeflags & UART_MF_COOKEDMODE)
        elmode = 1;
    else
        elmode = 0;

    /*
     * Call without data pointer discards receive buffer.
     */
    if (buffer == 0) {
        ifs->if_rd_idx = ifs->if_rx_idx;
        return 0;
    }

    /*
     * Get characters from receive buffer.
     */
    for (rc = 0; rc < size;) {
        if (ifs->if_rd_idx == ifs->if_rx_idx) {
            if (rc)
                break;
            while (ifs->if_rd_idx == ifs->if_rx_idx) {
                if (SciH8Input(dev)) {
                    return 0;
                }
            }
        }
        ch = ifs->if_rx_buf[ifs->if_rd_idx++];
        if (elmode && (ch == '\r' || ch == '\n')) {
            if (ifs->if_last_eol == 0 || ifs->if_last_eol == ch) {
                ifs->if_last_eol = ch;
                *cp++ = '\n';
                rc++;
            }
        } else {
            ifs->if_last_eol = 0;
            *cp++ = ch;
            rc++;
        }
    }
    return rc;
}

/*!
 * \brief Write to device.
 */
int SciH8Put(NUTDEVICE * dev, CONST void *buffer, int len, int pflg)
{
    int rc;
    IFSTREAM *ifs;
    UARTDCB *dcb;
    CONST u_char *cp;
    u_char lbmode;
    u_char elmode;
    u_char ch;

    ifs = dev->dev_icb;
    dcb = dev->dev_dcb;

    if (dcb->dcb_modeflags & UART_MF_LINEBUFFER)
        lbmode = 1;
    else
        lbmode = 0;

    if (dcb->dcb_modeflags & UART_MF_COOKEDMODE)
        elmode = 1;
    else
        elmode = 0;

    /*
     * Call without data pointer starts transmission.
     */
    if (buffer == 0) {
        rc = SciH8Flush(dev);
        return rc;
    }

    /*
     * Put characters in transmit buffer.
     */
    cp = buffer;
    for (rc = 0; rc < len;) {
        if ((u_char) (ifs->if_wr_idx + 1) == ifs->if_tx_idx) {
            if (SciH8Flush(dev)) {
                return -1;
            }
        }
        ch = pflg ? PRG_RDB(cp) : *cp;
        if (elmode == 1 && ch == '\n') {
            elmode = 2;
            if (lbmode == 1)
                lbmode = 2;
            ch = '\r';
        } else {
            if (elmode == 2)
                elmode = 1;
            cp++;
            rc++;
        }
        ifs->if_tx_buf[ifs->if_wr_idx++] = ch;
    }

    if (lbmode > 1 || (dcb->dcb_modeflags & UART_MF_NOBUFFER) != 0) {
        if (SciH8Flush(dev))
            rc = -1;
    }
    return rc;
}

int SciH8Write(NUTFILE * fp, CONST void *buffer, int len)
{
    return SciH8Put(fp->nf_dev, buffer, len, 0);
}

/*!
 * \brief Open a device or file.
 */
NUTFILE *SciH8Open(NUTDEVICE * dev, CONST char *name, int mode, int acc)
{
    NUTFILE *fp = NutHeapAlloc(sizeof(NUTFILE));
    UARTDCB *dcb;

    if (fp == 0)
        return NUTFILE_EOF;

    dcb = dev->dev_dcb;
    if (mode & _O_BINARY)
        dcb->dcb_modeflags &= ~UART_MF_COOKEDMODE;
    else
        dcb->dcb_modeflags |= UART_MF_COOKEDMODE;

    fp->nf_next = 0;
    fp->nf_dev = dev;
    fp->nf_fcb = 0;

    return fp;
}

/*!
 * \brief Close a device or file.
 */
int SciH8Close(NUTFILE * fp)
{
    NutHeapFree(fp);

    return 0;
}

/*@}*/