750-00004 Parallax Inc, 750-00004 Datasheet - Page 18

• Manufacturer Part Number: 750-00004
• Description: POWER SUPPLY 24VDC 600MA
• Manufacturer: Parallax Inc

Specifications of 750-00004

• Form: Wall Mount (2 Prong)
• Voltage - Output Per Connector: 24VDC
• Current - Output: 600mA
• Polarization: Positive Center
• Cord Plug: 2.1mm I.D. x 5.5mm O.D. x 12mm Female
• Voltage - Input: 120VAC
• Power - Output: 14W
• Transformer Type: Linear, Unregulated
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Efficiency: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

Back_To_Work:
Run_Task:
' -----[ Subroutines ]-----------------------------------------------------
Initialize:
Sometimes it is necessary to query a PLC for a particular piece of information. The example above shows
how to create two modes within one program. The default mode is the working mode, and it splits its
time into two functions: running the user program (which has been omitted for clarity), and checks the
serial port to see if there is an input from the master, (you). The second mode is invoked if the proper
wake up character is received from the master. Once in this mode, data will be reported if the master
sends a "?" command. If no command is received for a period of 5 seconds or more, the program will
automatically revert to the first mode (running the user program and monitoring the serial line).
Password Protection
PLCs typically control machinery. Quite often, these machines and/or the products that they make are
worth quite a bit of money.
variables that should not be changed, it is sometimes necessary to control access to the PLC. A common
way to do this is to utilize a password.
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' -----[ Program Description ]---------------------------------------------
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' -----[ Revision History ]------------------------------------------------
Parallax, Inc. • Stamp PLC (#30064) • Version 1.8 • 12/29/2003
LOOP UNTIL (keyIn = "X")
SEROUT 16, Baud, [CR, LF, "Returning to work"]
GOSUB Initialize
SEROUT 16, Baud, ["."]
GOTO Main
SEROUT 16, Baud, [CR, LF, "Working"]
RETURN
ENDSELECT
File....... Stamp PLC_Password.BS2
Purpose.... Typical PLC application whereby this unit listens for a
Author..... Parallax, Inc.
E-mail..... [e-mail]
Started.... 25 JUN 2003
Updated.... 25 JUN 2003
{$STAMP BS2}
{$PBASIC 2.5}
This program demonstrates how to periodically "listen" for a password
message on the serial port while performing another task. Once the
correct password is given, the password may be altered or cleared.
The password is stored in eeprom so it is non-volatile.
ENDIF
password on the serial port before allowing commands to be
parsed.
Given this, security is an issue.
' User task code goes here
' -- progress indicator
' setup for user task goes
'
goes here
To safeguard the program, and any
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