View source for Unit RPIFT5406

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=== Description ===
----

'''Raspberry Pi FT5406 Touch Driver unit'''

This is the touchscreen driver for the Official Raspberry Pi 7" Touchscreen. While this device uses a FocalTech FT5406 10 point capactive touchscreen controller it is actually connected to the GPU and not directly accessible to the ARM processor.
 
In order to make the touchscreen data available the GPU provides a memory based interface that can be read by polling an address returned from a mailbox call.
 
The Linux driver uses a thread to poll the data approximately 60 times per second so this driver does something similar.

=== Constants ===
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<div style="font-size: 14px; padding-left: 12px;">'''RPiFT5406 specific constants''' <code> RPIFT5406_* </code></div>
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{| class="wikitable" style="font-size: 14px; background: white;"
|-
| <code>RPIFT5406_TOUCH_DESCRIPTION = 'Raspberry Pi FT5406 Touch Controller';</code>
| Description of RPiFT5406 Touch device
|-
|colspan="2"|&nbsp;
|-
| <code>RPIFT5406_THREAD_NAME = 'RPiFT5406 Touch';</code>
| Name of the RPiFT5406 Touch polling thread
|-
|colspan="2"|&nbsp;
|-
| <code>RPIFT5406_MAX_POINTS = 10;</code>
| &nbsp;
|-
| <code>RPIFT5406_MAX_X = $FFF;</code>
| &nbsp;
|-
| <code>RPIFT5406_MAX_Y = $FFF;</code>
| &nbsp;
|-
| <code>RPIFT5406_MAX_Z = 0;</code>
| &nbsp;
|-
|colspan="2"|&nbsp; 
|-
| <code>RPIFT5406_SCREEN_WIDTH  = 800;</code>
| &nbsp;
|-
| <code>RPIFT5406_SCREEN_HEIGHT = 480;</code>
| &nbsp;
|-
|}
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=== Type definitions ===
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''To be documented''

=== Public variables ===
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''None defined''

=== Function declarations ===
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'''Initialization functions'''

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<pre style="border: 0; padding-bottom:0px;">procedure RPiFT5406Init;</pre>
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Initialize the RPiFT5406 unit and create, register and start the device</div>
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{| class="wikitable" style="font-size: 14px; background: white;"
|-
! '''Note'''
| Called only during system startup
|-
|}
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'''RPiFT5406 touch functions'''

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<pre style="border: 0; padding-bottom:0px;">function RPiFT5406TouchStart(Touch:PTouchDevice):LongWord;</pre>
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Implementation of TouchDeviceStart API for RPiFT5406</div>
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{| class="wikitable" style="font-size: 14px; background: white;"
|-
! '''Note'''
| Not intended to be called directly by applications, use TouchDeviceStart instead
|-
|}
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<pre style="border: 0; padding-bottom:0px;">function RPiFT5406TouchStop(Touch:PTouchDevice):LongWord;</pre>
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Implementation of TouchDeviceStop API for RPiFT5406</div>
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{| class="wikitable" style="font-size: 14px; background: white;"
|-
! '''Note'''
| Not intended to be called directly by applications, use TouchDeviceStop instead
|-
|}
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<pre style="border: 0; padding-bottom:0px;">function RPiFT5406TouchExecute(Touch:PRPiFT5406Touch):PtrInt;</pre>
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Thread function for the RPiFT5406 Touch controller driver. The thread polls the memory touch buffer approximately 60 times per second for new touch data and inserts received touch points into the buffer of the passed device</div>
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{| class="wikitable" style="font-size: 14px; background: white;"
|-
! '''Note'''
| Not intended to be called directly by applications
|-
|}
</div></div>
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