GE T2100, Руководство по обслуживанию

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Revision A GE T2100 Treadmill 5-13
2021403-031
Theory of Operation: Processor Board (PCB) Theory
ESD and EMI Compatibility
The connectors on this board have current limiting resistors and filtering
capacitors on almost every signal to prevent EMI from escaping this
board. These components also limit rise-time and voltages which may
come from ESD or other noise sources.
Isolation
The drive serial communication circuit, drive, and elevation control
signals share a common ground that may be attached to the chassis. The
Host serial communication, ESTOP connection, calibration button, and
control circuitry are all placed on isolated power. This ground allocation
separates the micro controller ground from the chassis ground by using
opto-couplers allowing at least 4KVAC without breakdown and double
isolation for 250 VAC
Operation
The processor board’s main task is to monitor the proper GE T2100
Treadmill operation by testing selected variables from the system. In
case of any variable operating out of specs, the firmware will first detect
the event, then log it, and finally stop any further operation. For speed
control, the processor board will act as a translator between the host and
the drive system. For elevation control, the board will act as a controller
by providing proper calibration and by handling elevation increment/
decrement commands received via the host serial port.
Start-Up Sequence
Immediately after power-up, the processor board will start a self-test
procedure where the following subsystems are tested: internal RAM,
board temperature, external serial flash memory, host communication,
drive communication, control signals, elevation, power supply, ESTOP,
and calibration. If any of the above tests result in an abnormal condition,
the processor board will stop any further operation and will log the
condition on its external flash memory. After all subsystems are
determined to be operating properly, the processor board will enter in a
standby state until a serial command is received from the host. The
processor board will wait until the host sends a belt start command
"B<CR>" to start operations. After receiving the belt start command, the
board will enable the drive by activating the D_DRIVE_EN signal on J2.
After this action, the drive will be activated and in standby state. At this
moment elevation and speed control commands can be sent to the
processor board.
Elevation Control
The elevation control process works as follows: The host will send an
elevation command "GXXX0<CR>" to the processor board, the micro
controller will interpret this data in order to enable the elevation