MaxiProx
®
Installation Guide Part No. 5375-901, Rev E.1
March 2012 Page 19 of 19
© 2008-2012 HID Global Corporation. All rights reserved.
4.3 RS232 and RS422 Card Message Specification
(Send Mode Only)
When Access Cards (transponders) are presented to the MaxiProx reader, the reader sends a
message. The message is in the following format:
CCDDDDDDDDDDXX<CR><LF>
^ First character sent
All characters C, D and X are ASCII encoded, hexadecimal digits. (i.e., the hex value 7 is sent as an
ASCII character 7 or the hex value E is sent as an ASCII character E).
The CC field is reserved for use by HID Global Corporation. The valid values are 00 through 7F.
The DDDDDDDDDD field is the transponders (Access Card) data. The valid values are 0000000000 through
1FFFFFFFFF (ASCII).
The XX field is a computed checksum. The checksum is calculated by first grouping the message data
into the pairs CC DD DD DD DD DD. Each pair of characters represents one byte of data. Then each pair of
characters is converted from ASCII to their respective hex values. At this point, the 6 bytes are added
together. The checksum is equal to the least significant 8 bits of the result.
<CR> is the ASCII code for a carriage return. (0D hex)
<LF> is the ASCII code for a line feed. (0A hex)
For example, if the MaxiProx reads a transponder (Access Card) that contains the value CC=00 and
DDDDDDDDDD=01234ABCDE, the reader will report the ASCII message 0001234ABCDE08<CR><LF>.
Note: Each of the characters is ASCII encoded. The actual bytes (hex value) that are sent to the host
are:
<30><30><30><31><32><33><34><41><42><43><44><45><30><38><0D><0A>
The checksum was computed by adding 00 + 01 + 23 + 4A + BC + DE = 208 hex. The checksum is the least
significant 8 bits of this result or 08 hex. The communications settings are 9600-75Hz BAUD, 8 bits, 1
stop bit, no parity.
To Previous Page
Loading...
Need help?
General
