about sio.c

I normally let the file names tell which device in the chip that it services.

In some situations, it may be a general file for all devices of the same type.

In some situations, there is a separate source file for uart0 and uart1 because they may differ fundemantally all the way from the interrupt service routine.

I did see this thread earlier but skipped past it since I didn't really know how to phrase myself in just a semi-provocative way and I didn't have the time to write a long answer.

Anyway - a file sio.c most probably contains accesses to some parts of the processor. In the case of a C51 project, it is more than likely that the code references a couple of special function registers (SFR) that can be located in the datasheet for the processor, or in the general documentation for the 8051 architecture.

These magic SFR should quickly tell what the file does - even if it is called mrn (My Random Name). Sometimes the file name is easy to decode. Sometimes hard. But you can get a lot of hints by looking in the file.

I don't think too many people on this forum would bet against a serial I/O module - most porbably for the UART.

I normally let the file names tell which device in the chip that it services.

In some situations, it may be a general file for all devices of the same type.

In some situations, there is a separate source file for uart0 and uart1 because they may differ fundemantally all the way from the interrupt service routine.

I did see this thread earlier but skipped past it since I didn't really know how to phrase myself in just a semi-provocative way and I didn't have the time to write a long answer.

Anyway - a file sio.c most probably contains accesses to some parts of the processor. In the case of a C51 project, it is more than likely that the code references a couple of special function registers (SFR) that can be located in the datasheet for the processor, or in the general documentation for the 8051 architecture.

These magic SFR should quickly tell what the file does - even if it is called mrn (My Random Name). Sometimes the file name is easy to decode. Sometimes hard. But you can get a lot of hints by looking in the file.

I don't think too many people on this forum would bet against a serial I/O module - most porbably for the UART.