IS-S04G1LC-S User Manual
IS-S04G1LC User Manual C Page 12 of 13
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9. Key Terms & Definitions
Host
Any computer, terminal, or other device that can communicate over the
USB line.
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 are sent by using this format.
2.
ASCII HEX 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 addresses and most data are sent using this format.
Address
A two-byte value ranging from 0001H to 000AH representing the 10
memory locations for images on the flash memory.
