Programming Guide

CHUMP Reference Guide
26
Ra
Name
Read user data from any tag.
Description
Read user data from any tag in field. If no “a:” sequence is
included, the first block (block 00) is read. If no “l:” sequence
is included, only one block is read.
Type
Tag command with reply
Format
}Ra[,a:<blk addr>][,f:xx][,l:<# blks>];
<FCS><CRLF>
}Ra[,a:<blk addr>][,f:xx][,l:<# blks>]!
<CRLF>
where:
a:<blk addr> is the tag-specific block adderess.
f:xx is an optional opcode override for Protocol B.
l:<# blks> is the tag-specific block size (1 or 4).
Return Message
{Ra,l:xx,d:<data>;<FCS><CRLF>
{Ra[,e:xx;]*;<FCS><CRLF>
NOTE: ISO 18000-6A provides for a Fast Dialog Mode. In this
mode, an inventory round is suspended when a tag is found
to allow dialog with the tag (the tag is in a selected state
during the dialog). A typical sequence is as follows:
}Rd,t:IS186A,f:04!<CRLF>
{Rd,d:<tag id>,f:04;<FCS><CRLF> <tag dialog>
{Tn,f:04!<CRLF> <resume inventory>