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EasyPIC6 Development System
MikroElektronika
page
20.0. Additional I/O Ports
The SPI communication lines and MCP23S17 circuit provide the EasyPIC6 development system with a means of increasing the number of
available I/O ports by two. If the port expander is connected over the DIP switch SW6, the following pins RA2, RA3, RC3, RC4 and RC5 will
be used for SPI communication and thus cannot be used as I/O pins. Switches INTA and INTB on the DIP switch SW10 enable interrupt.
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Figure 20-3
: Port expander schematic
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Jumpers J18 and J19 in the upper position
Figure 20-1
: Port expander
DIP switch connecting port
expander to the microcontroller
Jumper for selecting
pull-up/pull-down resistor
PORT0
PORT1
Figure 20-2
: DIP switch SW6 when port
expander is enabled
