User Manual

Software Design

ZSTAR3 Reference Design Manual, Rev. 0.1

Freescale Semiconductor 5-43

Preliminary

Table 5-9. Legend of colors

5.4.4 Burst mode

A new mode of ZSTAR USB communication is burst mode. The Burst mode is designed to symplification

reading process of new acceleration data. In burst mode USB Stick is sending all new received acceleration

data from individual enabled sensor boards without any request command from PC.

Burst mode content:

• time of receive - 24bits time information with 4 us step

• manage byte - contain actual datarate, mode 8/16bits and index of Sensor board

• acceleration data + data status - this field can be multiply repeat up to 4 samples depends on actual

datarate

• Status - contains information about select g range, buttons and events of last sample

Burst mode frame formats examples:

[ttttttmmxxyyzzddss] - 8 bits 30Hz frame

[ttttttmmxxxxyyyyzzzzddss] - 16 bits 30Hz frame

[ttttttmmxxxxyyyyzzzzddxxxxyyyyzzzzddxxxxyyyyzzzzddxxxxyyyyzzzzddss] - 16 bits 120Hz frame -

worest case of communication

where is: t - receive time, m - manage byte, x- accelariotion in X axis, y- accelariotion in Y axis, z-

accelariotion in Z axis, d - data status byte, s - frame status byte, [ - start char and ] is end char of frame.

Real example of burst mode frame:

”[BBBCDCA0D0001400400000D6002C00410000D9002D003D0000E1002F003D000020]”.

5.4.5 Network Lock feature of ZSTAR3 protocol

The ZStar3 RF protocol brings a new network lock function.This feature allow provide more ZSTAR3

networks in one RF space. For more details check section 5.3.2.1, “Network Number(NetNum).

5.4.6 Semiautomatic Self-Calibration

For the purpose of easier semiautomatic calibration of the ZSTAR demo with out PC GUI, the additional

Calibration command ‘Q’ (0x51) has been added. This command is usually issued over terminal (e.g.

HyperTerminal) software.

Legend

Red Direction PC -> USB Stick

Blue Direction USB Stick -> PC, regular

data