OS-9 for the Prospector P1100 Board Guide
OS-9 for the Prospector P1100 Board Guide
OS-9 for the Prospector P1100 Board Guide
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MAUI Driver Descriptions<br />
UCB<br />
Audio<br />
Opening <strong>the</strong> /ucb device will per<strong>for</strong>m basic chip initialization. Normally this<br />
is not necessary, unless ano<strong>the</strong>r driver is written to control part of <strong>the</strong><br />
UCB1200 functions. This is <strong>the</strong> case <strong>for</strong> audio. The MAUI Sound driver<br />
sd_ucb1200 will open /ucb to per<strong>for</strong>m chip initialization. In this way, <strong>the</strong><br />
MAUI Sound driver play audio and this driver can control <strong>the</strong> touch screen<br />
at <strong>the</strong> same time.<br />
This portion of <strong>the</strong> driver is not implemented since <strong>the</strong> MAUI Sound driver<br />
sd_ucb1200 already exists. sd_ucb1200 and this driver can co-exist.<br />
Touch Screen<br />
This portion of <strong>the</strong> driver controls <strong>the</strong> touch screen operation. When<br />
pressure is applied to <strong>the</strong> touch screen, a hardware interrupt is raised, and<br />
this driver's interrupt service routine will execute. A system state alarm,<br />
<strong>the</strong>n, will fire at regular intervals to sample data from <strong>the</strong> touch screen.<br />
When pressure is removed, <strong>the</strong> alarm stops. This mechanism leaves <strong>the</strong><br />
UCB1200 in a low power state until <strong>the</strong> user presses <strong>the</strong> touch screen. The<br />
alarm rate can be controlled in <strong>the</strong> ucb_touch descriptor.<br />
<strong>OS</strong>-9 <strong>for</strong> <strong>the</strong> <strong>Prospector</strong> <strong>P1100</strong> <strong>Board</strong> <strong>Guide</strong> 81<br />
B
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