User Manual

Medio S004 EVM
7.1.1 Customized ASCII Message Format
When a tag is read, its data are transmitted to the host in the form of an ASCII character frame.
Table 5: Customized ASCII Message Format (TAGSYS RFID Tag is read)
Start of Text
Header
String
Chip
Description
String
ID
End of
Message
String
End of Text
Description
<STX>
(0x02)
“TAGSYS-“
(Default)
Chip name
<CR/LF>
(Default)
<ETX>
(0x03)
I-Code
EPC
2 to 24 characters
I-Code
UID
2 to 16 characters
C270
(Philips I-
Code™-1)
2 to 16 characters
ISO15693 2 to 16 characters
S004 Optional Optional Optional Required Optional Optional
Medio S004 reader can decode all chips in Stand-alone mode. Only the ID field is required in the
return ASCII message. All other fields are optional. The ID field length is programmable; the default
lengths are given in Table 6.
Table 6: Default ID Field Lengths
Chip Type Default ID Field Length
I-Code EPC 24 (Total memory)
I-Code UID 10 (Memory area 1)
C270 (Philips I-Code™) chip 16 (Block 0 and Block 1)
ISO 15693 compliant 16 (UID)
7.1.2 Repetition Option
The reader constantly attempts to read any chips present in the field. When a chip ID is detected,
the reader can send the information to the host in one of 2 modes:
1. In “Repeated Read” mode, the reader returns a chip’s ID to the host with each successful
read operation.
2. In “Read Once” mode, the reader only returns the ID of a chip if the previous read
corresponds to a different chip, or if all reading attempts have failed 4 times (this feature
makes it possible to detect a chip’s potential exit out of the field).
October 2006 Revision 1.1 27/33