The old code only checks touch->max_x > touch->min_x but not touch->max_x == touch->min_x. Thus may lead to divided by zero error.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1782 bbd45198-f89e-11dd-88c7-29a3b14d5316

The old code forgot to drop the MSB in the very first byte retrieved from ads7843 after a control byte. This will lead to data corruption especially in 16-Clocks per conversion mode.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1781 bbd45198-f89e-11dd-88c7-29a3b14d5316

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1610 bbd45198-f89e-11dd-88c7-29a3b14d5316