IS-Dev Kit-2 Users Manual
7850 East Gelding Drive • Scottsdale, AZ 85260-3420
IS-Dev Kit-2 Users Manual A.doc
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2. Key Terms & Definitions
LCD Module NKK Switches SmartSwitch / SmartDisplay
Host Any computer, terminal, or other device that can communicate over RS232
line.
Controller A PCB assembly that controls one or more logic boards and the switches
associated with them. It communicates with a host over the RS232 line.
Logic Board A PCB assembly with “glue logic” for mounting switches. It is controlled by a
controller.
Byte An eight bit hex value ranging from 00H to FFH (Decimal 0 to 255). The bit
format of a byte is: (B7 B6 B5 B4 B3 B2 B1 B0) where B7 is most significant
and bit B0 is least significant bit.
Nibble/Hex digit A four bit value ranging from 0H to FH. A byte consists of two nibbles.
ASCII A byte value representing a symbol.
Communication There are two formats to transmit a byte:
format
1. Hex format - A hex byte is transmitted without any change to it. [xxH] will
be used to denote this.
All commands and some data sent by using this format.
2. ASCII format - Each nibble of the byte is converted to ASCII code and
sent as a byte. [xxAH] will be used to denote this.
For example, the hex byte 5AH is transmitted in two bytes, 35H and 41H.
The ASCII value for 5 is 35H and the ASCII value for A is 41H.
All pointers, all addresses and most data are sent using this format.
Pointer One byte. There is a pointer for each LCD Module. The value of a pointer is
a virtual address that refers to the 255 storage locations in the EEPROM (01H
to FFH). Each location has image data LED data, and attribute data. The
controller finds the actual address from this virtual address and uses the data
for the LCD modules.
