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<a name="1204411"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">11 Device information</font>
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<a name="1204412"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Two functions are provided to return information about the ST20 family of devices. <font size=2 face=Courier><strong>device_id</strong></font> returns the ID of the current device. <font size=2 face=Courier><strong>device_name</strong></font> takes a device ID as input and returns a brief description of the device.</font>
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<a name="1204413"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Device Identifiers are defined by the IEEE1149.1 (JTAG) Boundary-Scan Standard. This is a 32 bit number composed of a number of fields. OS20 defines a type to describe this, <font size=2 face=Courier><strong>device_id_t</strong></font>. This is a <font size=2 face=Courier><strong>union</strong></font> with three fields:</font>
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<p> <font size=2 face="Verdana, Arial, Helvetica, sans-serif"><li ><a name="1204417"> </a><font size=2 face=Courier><strong>id</strong></font> which allows the code to be manipulated as a 32 bit quantity,</font></p>
<p> <font size=2 face="Verdana, Arial, Helvetica, sans-serif"><li ><a name="1204418"> </a><font size=2 face=Courier><strong>jtag</strong></font> which views the value as defined by the JTAG standard,</font></p>
<p> <font size=2 face="Verdana, Arial, Helvetica, sans-serif"><li ><a name="1204419"> </a><font size=2 face=Courier><strong>st</strong></font> which views the value as used by STMicroelectronics. This breaks the device code down into a family and a device code.</font></p>
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<a name="1204420"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><font size=2 face=Courier><strong>jtag</strong></font> and <font size=2 face=Courier><strong>st</strong></font> are <font size=2 face=Courier><strong>structs</strong></font> of bit-fields, which allows the elements to be accessed symbolically.</font>
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