Texas Instruments TLV320AIC3109EVM-K, Руководство пользователя

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GPIO Capability
59 SLAU738 – September 2017
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USB-MODEVM Protocol
The return packet should be
[0] 0x21
[1] 0xA0
[2] 0x02
[3] 0x05
[4] 0xAA
[5] 0x55
assuming that the values previously written starting at Register 5 were actually written to the device.
I.2 GPIO Capability
The USB-MODEVM has seven GPIO lines. Access them by specifying the interface to be 0x08, and then
using the standard format for packets—but addresses are unnecessary. The GPIO lines are mapped into
one byte (see
Table 14 ):
Table 14. GPIO Pin Assignments
Bit 7 6 5 4 3 2 1 0
x P3.5 P3.4 P3.3 P1.3 P1.2 P1.1 P1.0
Example: write P3.5 to a 1, set all others to 0:
[0] 0x18
--> write, GPIO
[1] 0x00
--> this value is ignored
[2] 0x01
--> length - ALWAYS a 1
[3] 0x00
--> this value is ignored
[4] 0x40
--> 01000000
The user may also read back from the GPIO to see the state of the pins. Consider if the previous example
was written to the port pins.
Example: read the GPIO
[0] 0x08
--> read, GPIO
[1] 0x00
--> this value is ignored
[2] 0x01
--> length - ALWAYS a 1
[3] 0x00
--> this value is ignored
The return packet should be:
[0] 0x28
[1] 0x00
[2] 0x01
[3] 0x00
[4] 0x40
I.3 Writing Scripts
A script is simply a text file that contains data to send to the serial control buses. The scripting language is
quite simple, as is the parser for the language. Therefore, the program is not very forgiving about mistakes
made in the source script file, but the formatting of the file is simple. Consequently, mistakes should be
rare.