Subject: Re: silo overflows
To: msaitoh <>
From: Michael L. VanLoon -- <>
List: port-i386
Date: 04/02/1996 22:51:47
> > > Does someone implement "auto flow control on 16550a (with enable AFE bit)
> > > to com.c?

> > Is this feature supported by all 16550's?

> Sorry, I don't know. TI's 16550a (TL16550C) have this feature.
>I don't know another 16550 (for example, I have GoldStar's 16550!)
>have this.

> > How does one enable it?

>AFE bit is located in MCR register.
>  /* modem control register */
>+ #define	MCR_AFE		0x20	/* Auto Flow Enable */
>  #define	MCR_LOOPBACK	0x10	/* Loop test: echos from TX to RX */
>  #define	MCR_IENABLE	0x08	/* Out2: enables UART interrupts */
>  #define	MCR_DRS		0x04	/* Out1: resets some internal modems */

This bit is undefined in the data sheet for the Startech ST18C550
(their version of the NS16C550), which I believe their dual and quad-
port chips are based on.

  Michael L. VanLoon                       
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