High Country Tek DVC80 - Manual (Page 28)

P/N: 021-00154, Rev. A.6 - updated for V4.7 Tools Page | 28
3.9 DVC Program Loader Monitor Password Implementation
The password scheme is implemented to protect customers from software vandalism or unskilled users. First,
the passwords are defined using the Programming Tool and are downloaded into the DVC5/7/10 when the
project files are loaded. Next, the Program Loader Monitor asks you to enter a password for the level of access
you wish to have to the run time environment. The Program Loader Monitor has 3 levels of password protection.
The level of the password entered in the Program Loader Monitor determines your access and ability to issue
commands. The three levels are 1: Send Changes, 2: Load Applications, 3: Load BIOS. Higher numeric levels
include all of the abilities of the lower levels. If no password is entered when the Program Loader Monitor is run
then default access is given to the user to view the status of the DVC5/7/10, factory information, EE memory
(non-volatile memory where program variables can be stored in the event of power failure) and DVC expansion
modules. However, if all password fields are left blank in the Programming Tool, level 3 accesses is given by
the Program Loader Monitor.
Level 1: Send Changes
This level allows the user to view/send changes to the Output Groups, Analog Inputs, and I/O Functions. The
user can also export memory to a file and send changes to the EE memory.
Level 2: Load Application
This level allows the user to download a new application to the DVC.
Note: DVC software tools do not allow reading back programs stored in the DVC, so additional read back
protection is not required.
Level 3: Load BIOS
This level allows the user to make changes to the Factory Information settings. These settings include MAC ID,
CAN Bus type and CAN Bus baud rate. These settings will be explained later.
This level allows the user to download a BIOS file to the DVC5/7/10. The BIOS (i.e. kernel) is the HCT supplied
code that controls the execution of the DVC application and provides services to the application. It executes the
.pgm file code, monitors and controls the entire user configured input/outputs and schedules the execution of
the Always and logic sequence code.
3.10 Digital Inputs and Programmable LEDs
Eight digital inputs are provided in the DVC10 controller and three and four for the DVC7 and DVC5
respectively. You use the Program Loader Monitor to interrogate the digital inputs on the DVC7. On the
DVC5/10 modules each input has an associated LED. In addition the DVC5 has four programmable LEDs. To
illuminate these DVC5 LEDs in a specific pattern to indicate an error condition for instance you use the
keywords DVCLED_1, DVCLED_2, DVCLED_3 and DVCLED_4 to turn an LED on or off. DVCLED_4 = true
will illuminate the fourth LED on the DVC5 module.
All of the controllers have a programmable red status LED for indicating error conditions your application
detects.
Digital inputs are set by the opening or closing of a switch during system operation. The activation of a switch
presents a voltage waveform to a DVC5/7/10 digital input pin. The DVC hardware and software interpret the
waveform and convert it to a true or false value for the application program. The true or false value (> 0 or 0
numeric value respectively) is passed to the application program via a program variable with the name of the
input. Your application program control logic then determines what to do given this input state.