[WriteLog] serial interface PCI expansion boards

[Joe Subich, K4IK]

> Dave is correct. I was wrong when I said it was bit banging.
> 
> A more detailed reference to the 16550 is
> http://www.national.com/ds/PC/PC16550D.pdf.
> 
> This doc even includes some timing charts for baudot!
> 
> Any serial card using the 16550 or greater should work fine.
> 

Unfortunately, some of the 16550 "work alike" UARTs are not ... 
they either fail to support the five bit mode in their internal 
microcode or the board designers fail to implement the support 
hardware (clock generator, etc.).  

As Ron says, check your card first if you can.