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Efficient Multi-port Serial Device Driver

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Efficient Multi-port Serial Device Driver

Postby rahil » Wed Jun 10, 2009 2:25 pm

Hi.

I am trying to develop a multi-port serial port driver for a serial card. I wanted to know can we directly use the devc-ser8250 for our card? Is it an efficient multi-port driver?

The serial card has 8 ports and the interrupts can be shared.
rahil
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RE: Efficient Multi-port Serial Device Driver

Postby maschoen » Wed Jun 10, 2009 6:27 pm

If your card uses standard UARTS then the devc-ser8250 will work. That includes 8250, 16450, 16550's and probably some newer ones. What do you mean by efficient?
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Re: RE: Efficient Multi-port Serial Device Driver

Postby rahil » Thu Jun 11, 2009 5:27 am

maschoen wrote:If your card uses standard UARTS then the devc-ser8250 will work. That includes 8250, 16450, 16550's and probably some newer ones. What do you mean by efficient?


The device is based on the 16C554 / 16C654 quad serial port IC.This device contains 4
identical sets of registers, one for each port, and is compatible with the standard PC serial
port. The 16C554 has 16-byte FIFOs for each port and operates up to 115.2kbaud, while the
16C654 has 64-byte FIFOs and operates up to 460.8kbaud. I meant efficient as able to handle the interrupts equally well, no loss of data and no unnecessary delays in handling read/write requests.
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RE: Re: RE: Efficient Multi-port Serial Device Driver

Postby maschoen » Thu Jun 11, 2009 7:49 am

My guess is that devc-ser8250 will work just fine. The 16C554 sounds like 4 16550's. I never worked with a 64-byte FIFO but it's been a while. Unless you concoct something foolish, like a poorly written interrupt handler at a higher priority, you should have no trouble, even at the highest baud rates.
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