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The New Zune HD has a release date – fall of 2009. The New Zune HD has and OLED touchscreen screen display that evidently shows sharper images for better viewing. Zune HD is pretty much Microsoft’s answer to Apple’s iPod Touch. And ain’t that good for millions of electronic consumers?
Zune HD also has the following [...] … More Info

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Image leak suggest new model coming

Microsoft is set to release a new version of its MP3 player, the Zune, in America gadget site Engadget is reporting.
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Read Microsoft Zune HD inbound on Pocket-lint now

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If you haven’t heard, Microsoft recently had a huge fiasco involving almost ALL of their 30gb Zune’s (the Microsoft equivalent of an Apple iPod).  Two days ago on December 31, 2008, all of the 30gb versions of the Zune crashed simultaneously and would not turn back on.

There are frequent stories of iPods crashing and bricking but never of ALL of them crashing at the same time.  Given the proximity of the incident to the New Years, many suspected a bug with the date handling.  And as it turns out, that is exactly correct.

Taking a look at the source code, we find the following offending function:

BOOL ConvertDays(UINT32 days, SYSTEMTIME* lpTime)
{
    int dayofweek, month, year;
    UINT8 *month_tab;

    dayofweek = GetDayOfWeek(days);

    year = ORIGINYEAR;

    while (days > 365)
    {
        if (IsLeapYear(year))
        {
            if (days > 366)
            {
                days -= 366;
                year += 1;
            }
        }
        else
        {
            days -= 365;
            year += 1;
        }
    }

    month_tab = (UINT8 *)((IsLeapYear(year))?
monthtable_leap : monthtable);

    for (month=0; month<12; month++)
    {
        if (days <= month_tab[month])
            break;
        days -= month_tab[month];
    }

    month += 1;

    lpTime->wDay = days;
    lpTime->wDayOfWeek = dayofweek;
    lpTime->wMonth = month;
    lpTime->wYear = year;

    return TRUE;
}

Anyone spot the bug?  Here’s a hint, it’s in the leap year handling:

while (days > 365)
{
    if (IsLeapYear(year))
    {
        if (days > 366)
        {
            days -= 366;
            year += 1;
        }
    }
    else
    {
        days -= 365;
        year += 1;
    }
}

The bug creeps up on the last day of a leap year (day 366).  The function goes into an infinite loop since the day 366 is too large to break out of the while loop but not large enough to execute the nested if statement.

This is why the Zunes crashed and were unable to boot up since this function gets called at boot up. The simplest way to fix this bug is to add an else clause to the nested if function to break out of the loop.

        if (days > 366)
        {
            days -= 366;
            year += 1;
        }
        else
        {
            break;
        }

The announced solution to this problem from Microsoft is to simply wait until the next day and the Zune works again… until the last day of the next leap year!  I’m not sure why this bug only affects the 30gb version since I would assume all versions of the Zune to use the same firmware.

Regardless, this is definitely a PR disaster for Microsoft and not one that I see them recovering from quickly.  They need to release a firmware update and get everyone to update (not an easy task).  Personally, I don’t own a Zune but I will no longer consider purchasing one.  I guess it’s going to be Apple products for me, even though I’m not Apple’s biggest fan.

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