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GPIO
The CT Board offers on the 4 general purpouse ports the following functions:
- 4 general purpouse I/O ports
- 32 memory mapped output pins
- 32 memory mapped input pins
- 2 general purpouse I/O ports, directly connected to MCUs Port A and B
- External interface to SRAM bus.
GPIO over CPLD
Each of the 4 GPIO ports contains 8 ouput and 8 input pins. The ports are not as fast as the integrated GPIO ports of the microcontroller.
Registers
Input
Output
Diagram
GPIO over MCU
These two ports are directly connected to the GPIO ports A and B on the microcontroller.
All functions of theese GPIO ports are available.
Diagram
External Memory Bus
The CT Board is connected to the microcontroller over SRAM interface. This interface is also available on ports P1..4.
Full Bus
The full interface is connected.
Pin Out
Visualization on Oscilloskope
For educational purpouse there is a mode to visualize the bus on a oscilloskope.
The ports are specially configured to directly plug in the logic probe of a Tektronix logic analyzer.