misc_usbsevseg.rst (1561B)
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