User's Manual

MaxStream 9XStream™ Wireless OEM Module Manual v2.8

Confidential and Proprietary, ©MaxStream, Inc. 2001

Glossary

AT commands – A set of commands that can be used to customize and

configure the 9XStream module to meet specific needs. AT commands are sent

via a serial communications program such as HyperTerminal.

Binary commands – A set of commands used to configure the 9XStream

module. Binary commands are sent with RTS/CMD asserted. The RT command

must be used to enable binary programming prior to using binary commands.

Multiple Binary commands can be issued sequentially while RTS/CMD is

asserted.

Clear to send – See CTS pin.

CMOS logic – Logic levels used by the 9XStream module (0-5V).

Command Mode – A mode of operation, which manually modifies the

configurable parameters of the 9XStream module. Both Binary and AT

command modes are available.

Command table – Table containing 23 currently implemented commands. This

table lists all of the adjustable parameters along with a brief description of each.

CRC – See Cyclic Redundancy Check.

CTS pin – The low-asserted Clear To Send pin (Pin 1) provides flow control

for the 9XStream module. When CTS is asserted (low), serial data can be sent to

the module for transmission. If the module is unable to transmit the data, CTS

may de-assert (high) once the data buffer nears capacity to prevent buffer

overflow.

Cyclic redundancy check (CRC) – Used by the 9XStream module to ensure

data integrity during transmission. A CRC is computed on the bits to be

transmitted over-the-air and sent with each data packet. The CRC is recomputed

by the receiver and compared with the original CRC bits. The packet is valid if

the receiver CRC matches the CRC computed by the transmitter.

Cyclic sleep – Sleep Mode setting in which the module enters a low-power state

and awakens periodically to determine if any transmissions are being sent.

Data buffer – Collects incoming serial data prior to over-the-air data

transmission. The data buffer can hold up to 132 bytes at a given time. When

the buffer fills to 115 bytes, the Clear To Send (CTS) pin is de-asserted to stop

the flow of incoming serial data.

Data packets – A grouping of data to be sent over-the-air. Each data packet

contains a header and data that is collected from the data buffer. The size of the

packets varies up to 64 bytes depending on how many bytes of data are in the

data buffer.