Symbol MR 100, User Manual, Page: 9 / 21

Byte Stream Protocol with MR 100
MR 100 User Manual Page: 8
MR 100 User Manual
C h a p t e r 3 .
B
Y T E
S
T R E A M
P
R O T O C O L W I T H
M R 1 0 0
This chapter gives a brief introduction to Byte Stream Protocol and how it can be used to communicate with the MR
100 reader. If you are looking for more details of Byte Stream Protocol and how it can be used with other Symbol
Readers refer to Matrics API Programmers Manual.
3.1. Byte Stream and MR 100
Byte stream protocol can be used to send data to the host using a 2 wire serial link (RS-232) or TTL as factory option at
the following Baud Rates:
ƒ 19200
ƒ
38400
ƒ
57600
ƒ 115200
3.2. Generalized Request and Response Packets described
The byte stream packet follows generalized packet format for request and response packet. This section describes the
packet format which most request and response examples in this document will use. In practical implementation, most
of the times, these packets are arrays of bytes where elements are arranged as per specified format.
A general request packet that is being sent to MR 100 over host interface must be formatted as follows:
Field Number of Bytes
(Size) Value Description
SOF 1 0x01 Start Of Frame
Node Address 1 0~0x1F i.e. 0 to 31. Node address that had been set on the reader
Packet Length 1 See Description Size of the packet that is being sent. This should not
include the size of SOF but should include the size of CRC.
Command 1 See Description Each Reader API Command corresponds to a number. This
number tells the reader which command to fire. Populate
this byte with the value of the command which you want
the reader to fire.
Data Variable See Description Depending upon the command you are executing you may
need to send different number of bytes formatted
differently. See the definition of the command you want
to execute for more details. A Typical Request data
packet can be 0 to 64 bytes.
CRC 2
(1 for LSB & 1 for
MSB)
Dependent Bitwise inversion of the 16-bit CCITT-CRC of the packet
excluding SOF, with the LSB (Least Significant Byte) first.