36 lines
1.1 KiB
Text
36 lines
1.1 KiB
Text
#### 16550 CODE ####
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The 16550 Code in this repository was developed for the ATMega 2560, which is
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the Atmel AVR on the Arduino Megas from Revision 3 onwards.
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The following port Registers have been used for the following things on the AVR:
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- PORTF
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This Port-Register is used for the Data-Bus. It is in most usecases
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onedirectional, but if needed, for example for a feedback read, it can
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be used as bi-directonal
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- PORTE[0;2]
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This part of the Port-Register is used for the Address bus and is
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always driven by the AVR.
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- PORTE[3]
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This pin is used for the !WR pin of the 16550 UART and is always driven
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by the AVR. THE !WR pin is used to signal a write access.
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- PORTE[4]
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This pin is used for the !RD pin of the 16550 UART and is always driven
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by the AVR. The !RF pin is used to signal a read access.
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- PORTE[5]
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This pin is used for the MR pin of the 16550 UART and is always
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driven by the AVR. The MR pin is used to reset the IC.
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- PORTE[6]
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This pin is used for the !CS3 pin of the 16550 UART and is always
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driven by the AVR. The !CS3 pin is used to tell the cheip when data
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on the data and address bus is meant for it.
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