Changes
8255
,*On the ASIC PPI, Port B is always defined as input and Port C is always defined as output.
*On a real PPI chip, when the PPI control register is used (with bit7=1) to configure the ports, the output latches of all ports are reset to 0. The ASIC poorly emulates the PPI and does not reset these ports.
= Resources =
* [[Media:Intel8255A_datasheet.pdf]] PPI Datasheet (Intel)
* [[Media:PPI M5L8255AP-5.pdf]] PPI Datasheet (Mitsubishi)
* [[VHDL https://github.com/jotego/jt8255 JT8255] Verilog implementation of the 8255 PIO]]PPI