Conrad C-Control Pro Mega Series, Руководство пользователя

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35 C-Control Pro Mega Series
© 2008 Conrad Electronic
Note: Detailed information can be found in the IC manufacturer’s PDF files on the C-Control Pro
Software CD-ROM.
ADC Reference Voltage Generation
The Micro Controller is equipped with an analog-to-digital converter with a 10 Bit resolution. This
means that measured voltages can be represented by integral numbers from 0 through 1023. The
reference voltage for the lower limit is GND level, i. e. 0V. The reference voltage for the upper limit
can be selected by the user:
· 5V Operating Voltage (VCC)
· Internal Reference Voltage of 2.56V
· External Reference Voltage e. g. 4.096V generated by a Reference Voltage IC.
If x is a digital measuring value then the corresponding voltage value u is computed as follows:
u = x * Reference Voltage /
1024
Clock Generation
Clock generation takes place by a 14.7456MHz Quartz Oscillator. All time dependent actions within
the controller are derived from this clock frequency.
Reset
A Reset initiates the return of the Micro Controller system to a defined starting condition. In gerneral
the C-Control Pro Module knows two reset sources:
· Power-On-Reset: is automatically executed after the operating voltage is switched on.
· Hardware-Reset: is executed when the Module’s RESET (X2_3) is pulled to "low" and released
again by e. g. shortly pressing the connected Reset push button RESET1 (SW3).
A "Brown-Out-Detection" avoids that the Controller can enter undefined conditions in case of
dropping operating voltages.
Digital Ports (PortA, PortB, PortC, PortD, PortE, PortF, PortG)
The C-Control Pro Module provides 6 digital ports at 8 pins each and one digital port with 5 pins. To
the digital ports it is possible to connect e. g. push buttons with pull-up resistors, digital IC’s, opto
couples or driver circuits for relais. The ports can be addressed either separatly, i.e. pin by pin or
byte by byte. Each pin can either be input or output.
Note: Never connect two ports directly together which should simultaneously work as outputs!
Digital input pins are high-impedance or wired to internal pull-up resistors and transform an applied
voltage signal into a logical value. For this it is required that the voltage signal is within the limits
defined for TTL and CMOS ICs high or low levels. During further processing in the program the logical
values on the respective input ports are represented as 0 ("low") oder -1 ("high). Pins will take on the
values 0 or 1, Bytes from 0 to 255. Output ports are able to give out digital voltage signals by use of