The Hands-on XBEE Lab Manual

APPENDIX B

Hexadecimal Numbers and Checksums

The Digi X-CTU software that configures XBee modules uses hexadecimal values represented by digits 0–9 and letters A–F, which equal the decimal values 0 through 15. This hexadecimal numbering system provides an easy way to represent four-bit binary numbers that comprise only 1s and 0s. Each hex digit represents a 4-bit binary value, from 0000₂ through 1111₂, or from 0x0 to 0xF as shown in Table B.1. The prefix of zero followed by the letter x indicates a value expressed in the hexadecimal numbering system. To represent an 8-bit byte, people use two hex digits such as 0x5E, which corresponds to 94₁₀, or 01011110₂. Two-digit hex values range from 0x00 to 0xFF, or in binary from 00000000₂ to 11111111 ...