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