keyspan_usa49msg.h

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/*
    usa49msg.h

    Copyright (C) 1998-2000 InnoSys Incorporated.  All Rights Reserved
    This file is available under a BSD-style copyright

    Keyspan USB Async Message Formats for the USA49W

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

    1. Redistributions of source code must retain this licence text
    without modification, this list of conditions, and the following
    disclaimer.  The following copyright notice must appear immediately at
    the beginning of all source files:

            Copyright (C) 1998-2000 InnoSys Incorporated.  All Rights Reserved

            This file is available under a BSD-style copyright

    2. The name of InnoSys Incorporated may not be used to endorse or promote
    products derived from this software without specific prior written
    permission.

    THIS SOFTWARE IS PROVIDED BY INNOSYS CORP. ``AS IS'' AND ANY EXPRESS OR
    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
    NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
    INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    SUCH DAMAGE.    

    4th revision: USA49W version

    Buffer formats for RX/TX data messages are not defined by
    a structure, but are described here:

    USB OUT (host -> USAxx, transmit) messages contain a 
    REQUEST_ACK indicator (set to 0xff to request an ACK at the 
    completion of transmit; 0x00 otherwise), followed by data:

        RQSTACK DAT DAT DAT ...

    with a total data length of 63.

    USB IN (USAxx -> host, receive) messages begin with a status
    byte in which the 0x80 bit is either:
                    
        (a) 0x80 bit clear
            indicates that the bytes following it are all data
            bytes:

                STAT DATA DATA DATA DATA DATA ...

            for a total of up to 63 DATA bytes,

    or:

        (b) 0x80 bit set
            indiates that the bytes following alternate data and
            status bytes:

                STAT DATA STAT DATA STAT DATA STAT DATA ...

            for a total of up to 32 DATA bytes.

    The valid bits in the STAT bytes are:

        OVERRUN 0x02
        PARITY  0x04
        FRAMING 0x08
        BREAK   0x10

    Notes:
    
    (1) The OVERRUN bit can appear in either (a) or (b) format
        messages, but the but the PARITY/FRAMING/BREAK bits
        only appear in (b) format messages.
    (2) For the host to determine the exact point at which the
        overrun occurred (to identify the point in the data
        stream at which the data was lost), it needs to count
        128 characters, starting at the first character of the
        message in which OVERRUN was reported; the lost character(s)
        would have been received between the 128th and 129th
        characters.
    (3) An RX data message in which the first byte has 0x80 clear
        serves as a "break off" indicator.
    (4) a control message specifying disablePort will be answered
        with a status message, but no further status will be sent
        until a control messages with enablePort is sent

    revision history:

    1999feb10   add reportHskiaChanges to allow us to ignore them
    1999feb10   add txAckThreshold for fast+loose throughput enhancement
    1999mar30   beef up support for RX error reporting
    1999apr14   add resetDataToggle to control message
    2000jan04   merge with usa17msg.h
    2000mar08   clone from usa26msg.h -> usa49msg.h
    2000mar09   change to support 4 ports
    2000may03   change external clocking to match USA-49W hardware
    2000jun01   add extended BSD-style copyright text
    2001jul05   change message format to improve OVERRUN case
*/

#ifndef __USA49MSG__
#define __USA49MSG__


/*
    Host->device messages sent on the global control endpoint:

    portNumber  message
    ----------  --------------------
    0,1,2,3     portControlMessage
    0x80        globalControlMessage
*/

struct keyspan_usa49_portControlMessage
{
    /*
        0.  0/1/2/3     port control message follows
            0x80 set    non-port control message follows
    */
    u8  portNumber,

    /*
        there are three types of "commands" sent in the control message:

        1.  configuration changes which must be requested by setting
            the corresponding "set" flag (and should only be requested
            when necessary, to reduce overhead on the USA26):
    */
        setClocking,    // host requests baud rate be set
        baudLo,         // host does baud divisor calculation
        baudHi,         // baudHi is only used for first port (gives lower rates)
        prescaler,      // specified as N/8; values 8-ff are valid
                        // must be set any time internal baud rate is set;
        txClocking,     // 0=internal, 1=external/DSR
        rxClocking,     // 0=internal, 1=external/DSR

        setLcr,         // host requests lcr be set
        lcr,            // use PARITY, STOPBITS, DATABITS below

        setFlowControl, // host requests flow control be set
        ctsFlowControl, // 1=use CTS flow control, 0=don't
        xonFlowControl, // 1=use XON/XOFF flow control, 0=don't
        xonChar,        // specified in current character format
        xoffChar,       // specified in current character format

        setRts,         // host requests RTS output be set
        rts,            // 1=active, 0=inactive

        setDtr,         // host requests DTR output be set
        dtr;            // 1=on, 0=off


    /*
        3.  configuration data which is simply used as is (no overhead,
            but must be specified correctly in every host message).
    */
    u8  forwardingLength,  // forward when this number of chars available
        dsrFlowControl, // 1=use DSR flow control, 0=don't
        txAckThreshold, // 0=not allowed, 1=normal, 2-255 deliver ACK faster
        loopbackMode;   // 0=no loopback, 1=loopback enabled

    /*
        4.  commands which are flags only; these are processed in order
            (so that, e.g., if both _txOn and _txOff flags are set, the
            port ends in a TX_OFF state); any non-zero value is respected
    */
    u8  _txOn,          // enable transmitting (and continue if there's data)
        _txOff,         // stop transmitting
        txFlush,        // toss outbound data
        txBreak,        // turn on break (cleared by _txOn)
        rxOn,           // turn on receiver
        rxOff,          // turn off receiver
        rxFlush,        // toss inbound data
        rxForward,      // forward all inbound data, NOW (as if fwdLen==1)
        returnStatus,   // return current status (even if it hasn't changed)
        resetDataToggle,// reset data toggle state to DATA0
        enablePort,     // start servicing port (move data, check status)
        disablePort;    // stop servicing port (does implicit tx/rx flush/off)
    
};

// defines for bits in lcr
#define USA_DATABITS_5      0x00
#define USA_DATABITS_6      0x01
#define USA_DATABITS_7      0x02
#define USA_DATABITS_8      0x03
#define STOPBITS_5678_1     0x00    // 1 stop bit for all byte sizes
#define STOPBITS_5_1p5      0x04    // 1.5 stop bits for 5-bit byte
#define STOPBITS_678_2      0x04    // 2 stop bits for 6/7/8-bit byte
#define USA_PARITY_NONE     0x00
#define USA_PARITY_ODD      0x08
#define USA_PARITY_EVEN     0x18
#define PARITY_1            0x28
#define PARITY_0            0x38

/*
    during normal operation, status messages are returned 
    to the host whenever the board detects changes.  In some
    circumstances (e.g. Windows), status messages from the
    device cause problems; to shut them off, the host issues
    a control message with the disableStatusMessages flags
    set (to any non-zero value).  The device will respond to
    this message, and then suppress further status messages;
    it will resume sending status messages any time the host
    sends any control message (either global or port-specific).
*/

struct keyspan_usa49_globalControlMessage
{
    u8  portNumber,         // 0x80
        sendGlobalStatus,   // 1/2=number of status responses requested
        resetStatusToggle,  // 1=reset global status toggle
        resetStatusCount,   // a cycling value
        remoteWakeupEnable,     // 0x10=P1, 0x20=P2, 0x40=P3, 0x80=P4
        disableStatusMessages;  // 1=send no status until host talks
};

/*
    Device->host messages send on the global status endpoint

    portNumber          message
    ----------          --------------------
    0x00,0x01,0x02,0x03 portStatusMessage
    0x80                globalStatusMessage
    0x81                globalDebugMessage
*/

struct keyspan_usa49_portStatusMessage  // one for each port
{
    u8  portNumber,     // 0,1,2,3
        cts,            // reports CTS pin
        dcd,            // reports DCD pin
        dsr,            // reports DSR pin
        ri,             // reports RI pin
        _txOff,         // transmit has been disabled (by host)
        _txXoff,        // transmit is in XOFF state (either host or RX XOFF)
        rxEnabled,      // as configured by rxOn/rxOff 1=on, 0=off
        controlResponse,// 1=a control message has been processed
        txAck,          // ACK (data TX complete)
        rs232valid;     // RS-232 signal valid
};

// bits in RX data message when STAT byte is included
#define RXERROR_OVERRUN 0x02
#define RXERROR_PARITY  0x04
#define RXERROR_FRAMING 0x08
#define RXERROR_BREAK   0x10

struct keyspan_usa49_globalStatusMessage
{
    u8  portNumber,         // 0x80=globalStatusMessage
        sendGlobalStatus,   // from request, decremented
        resetStatusCount;   // as in request
};

struct keyspan_usa49_globalDebugMessage
{
    u8  portNumber,         // 0x81=globalDebugMessage
        n,                  // typically a count/status byte
        b;                  // typically a data byte
};

// ie: the maximum length of an EZUSB endpoint buffer
#define MAX_DATA_LEN            64

// update status approx. 60 times a second (16.6666 ms)
#define STATUS_UPDATE_INTERVAL  16

// status rationing tuning value (each port gets checked each n ms)
#define STATUS_RATION   10

#endif