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Added port direction tests.

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This commit is contained in:
Thomas Harte 2017-08-07 19:36:55 -04:00
parent 7fbb455836
commit 4709ae80cb
1 changed files with 7 additions and 3 deletions
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10
Components/8255/i8255.hpp
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@ -46,9 +46,13 @@ template <class T> class i8255 {
uint8_t get_register(int address) {
switch(address & 3) {
case 0: return port_handler_.get_value(0);
case 1: return port_handler_.get_value(1);
case 2: return port_handler_.get_value(2);
case 0: return (control_ & 0x10) ? port_handler_.get_value(0) : outputs_[0];
case 1: return (control_ & 0x02) ? port_handler_.get_value(1) : outputs_[1];
case 2: {
if(!(control_ & 0x09)) return outputs_[2];
uint8_t input = port_handler_.get_value(2);
return ((control_ & 0x01) ? (input & 0x0f) : (outputs_[2] & 0x0f)) | ((control_ & 0x08) ? (input & 0xf0) : (outputs_[2] & 0xf0));
}
case 3: return control_;
}
return 0xff;