Matrix Orbital GLK240128-25, Техническое руководство

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35
File Upload Protocol
Once a bitmap or font file has been created and paired to its command it must be sent using a file
protocol developed specifically for Matrix Orbital displays. Once a file upload command has been sent
requesting a unique reference number and specifying the file size required, the display will respond
indicating whether it has enough room to save the file or not. As is the case throughout the upload
protocol, a response of 1 will indicate confirmation while an 8 corresponds to rejection and will
terminate the session.
Table 37: Upload Protocol Responses
Value Action Description
1 Confirm Transfer successful, upload continues
8 Decline Transfer failed, abort upload
Once a file is confirmed to fit within the display, the upload will begin. A protocol is used here to ensure
each byte is uploaded successfully. After each byte is sent, the module will echo it back to the host. It
should then be checked against the value originally sent before a confirmation byte of 1 is returned. If
the transmitted and echoed values do not match the upload should be aborted by sending a value of 8
instead. The upload will continue in this manner as indicated by the examples below which utilize
familiar font and bitmap files.
Table 38: Font Upload Protocol
Host Display Comments
254 Command Prefix
36 Upload Font File Command
1 Reference ID LSB
0 Reference ID MSB
31 Font File Size LSB
0 Font File Size
0 Font File Size
0 Font File MSB
1 Size Confirmation
5 First Font Data Byte
5 Echo Data Byte
1 Confirm Data Byte
... ... ...
96 Last Font Data Byte
96 Echo Data Byte
1 Confirm Data Byte
Table 39: Bitmap Upload Protocol
Host Display Comments
254 Command Prefix
94 Upload Bitmap File Command
1 Reference ID LSB
0 Reference ID MSB
5 Bitmap File Size LSB
0 Bitmap File Size
0 Bitmap File Size
0 Bitmap File MSB
1 Size Confirmation
5 First Bitmap Data Byte
5 Echo Data Byte
1 Confirm Data Byte
... ... ...
224 Last Bitmap Data Byte
224 Echo Data Byte
1 Confirm Data Byte
It should be noted that the display has a timeout setting of 2.1 seconds before it resets to prevent it
from hanging during the upload process. Upon reset, the values 254 and 212 will be returned to
indicate an error or lengthy delay has occurred in the upload process. If everything goes smoothly, the
protocol will end with the host transmitting a final confirmation byte and the font will be stored in the
display ready for any application.