Linux kernel mirror (for testing)
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tjh.dev
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linux
1=============================
2USB 7-Segment Numeric Display
3=============================
4
5Manufactured by Delcom Engineering
6
7Device Information
8------------------
9USB VENDOR_ID 0x0fc5
10USB PRODUCT_ID 0x1227
11Both the 6 character and 8 character displays have PRODUCT_ID,
12and according to Delcom Engineering no queryable information
13can be obtained from the device to tell them apart.
14
15Device Modes
16------------
17By default, the driver assumes the display is only 6 characters
18The mode for 6 characters is:
19
20 MSB 0x06; LSB 0x3f
21
22For the 8 character display:
23
24 MSB 0x08; LSB 0xff
25
26The device can accept "text" either in raw, hex, or ascii textmode.
27raw controls each segment manually,
28hex expects a value between 0-15 per character,
29ascii expects a value between '0'-'9' and 'A'-'F'.
30The default is ascii.
31
32Device Operation
33----------------
341. Turn on the device:
35 echo 1 > /sys/bus/usb/.../powered
362. Set the device's mode:
37 echo $mode_msb > /sys/bus/usb/.../mode_msb
38 echo $mode_lsb > /sys/bus/usb/.../mode_lsb
393. Set the textmode:
40 echo $textmode > /sys/bus/usb/.../textmode
414. set the text (for example):
42 echo "123ABC" > /sys/bus/usb/.../text (ascii)
43 echo "A1B2" > /sys/bus/usb/.../text (ascii)
44 echo -ne "\x01\x02\x03" > /sys/bus/usb/.../text (hex)
455. Set the decimal places.
46 The device has either 6 or 8 decimal points.
47 to set the nth decimal place calculate 10 ** n
48 and echo it in to /sys/bus/usb/.../decimals
49 To set multiple decimals points sum up each power.
50 For example, to set the 0th and 3rd decimal place
51 echo 1001 > /sys/bus/usb/.../decimals