Definitions – Matrix Orbital DD-DB1 LCD/VFD Dev Board User Manual
Page 46
Definitions
ASCII: American standard code for information interchange used to give standardized numeric codes to alphanumeric
characters.
BPS: Bits per second, a measure of transmission speed.
DOW: Dallas One-Wire protocol is similar to I
2
C providing reduced data rates at a greater distance. One wire is provided
for data, while two others supply power and ground. Matrix Orbital displays are only tested with non-parasitic
devices, those that do not draw power from the data line, however, some parasitic devices may work.
FFSTN: Double film super-twisted nematic in reference to an LCD. The addition of two layers of film between the STN
display and polarizer improves contrast.
GPO: General purpose output, used to control peripheral devices from a display.
GUI: Graphical user interface.
Hexadecimal: A base 16 number system utilizing the numerals and letters 0 through F to represent the values 0-15.
I
2
C: Inter-integrated circuit protocol employing a clock and data line to communicate a short distance at slow speeds
between a master and up to 128 addressable slave devices. A Matrix Orbital display is a slave device.
LCD: Liquid crystal display.
LSB: Least significant bit or byte in a transmission, the rightmost when read.
MSB: Most significant bit or byte in a transmission, the leftmost when read.
RS232: Recommended standard 232, a widely used serial protocol. A low level is -30V while a high is +30V.
SDA: Serial data line used to transfer data in I
2
C protocol. This open drain line should be pulled high through a resistor.
Nominal values are between 2K and 10K Ω.
SCL: Serial clock line used to designate data bits in I
2
C protocol. This open drain line should be pulled high through a
resistor. Nominal values are between 2K and 10K Ω.
STN: Super-twisted nematic in reference to an LCD. In a relaxed or nematic state, crystals orientate themselves in the
same direction and allow light to pass. In an excited state these crystals align to block light. Super-twisted crystals
move from 180 to 270 degrees between phases to providing contrast than TN models.
TTL: Transistor-transistor logic applied to a serial protocol. A low level is 0V while high logic is 5V.
USB: Universal Serial Bus protocol widely used in PCs.
VFD: Vacuum florescent display.
44