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[on:]

Just got word of this part from maxim-ic.com:

MAX14830
Quad Serial UART with 128-Word FIFOs and Internal Oscillator

Industry's First Quad UART
Scalable solution for industrial applications that is ideal for high channel count systems with the flexibility of adding channels
Simplified IO-link for master systems with the ability to synchronize the start of selectable UART's transmission by SPI™/I²C global commands
Works with up to four master IO-link PHY layer MAX14824s

I have a sample of single UART chip, MAX3100 in DIP, that I am looking forward to trying out via its SPI interface.
http://www.maxim-ic.com/datasheet/index.mvp/id/1731/t/al

I think I may be waiting on a 3.6864MHz Crystal for it, or it came already and I misplaced it.

[Reply #1 on:]

That quad sounds nice, I'll have to think of a project that needs one

______
Rob

[Reply #2 on:]

Check the data sheet, they have recommended some parts to go with it for serial port level drivers for lack of a better term.
Not available as samples yet tho, and only in 48 TQFN package.
http://datasheets.maxim-ic.com/en/ds/MAX14830.pdf  1-4MHz crystal. 1.8MHz only specific callout I saw.
The 128 word buffer per UART should make for smooth software operation I would think (vs sucking up a bunch of atmega RAM).

[Reply #3 on:]

Very nice, pity about the package, I'm getting better at soldering SMDs but that might be a problem.

_____
Rob

[Reply #4 on:]

http://pdfserv.maxim-ic.com/land_patterns/90-0129.PDF

Yes, 0.5mm pad spacing is a little tight.

Could get an adapter like this
http://www.dipmicro.com/store/PCB-LQFP48-DIP48G
even gets you pads for a crystal and caps to make a little unit out of it.

Order a few other items at the same time to get to $10 and get 10% disount too.

Got a friend who could mount it for you?

[Reply #5 on:]

Got a friend who could mount it for you?

No rush, I think I have enough projects on the go right now.

EDIT:
Actually now that I think about it, I made a plug-in board for a popular Z80-basedcomputer in the 80s. This computer had no real serial ports just bit-banged serial, so my board replaced the processor with a PCB that relocated the Z80 and added an SIO to give two UARTS and an RTC. Maybe an equivelent for a 328-based Arduino wouldn't be a bad idea.

______
Rob

[Reply #6 on:]

With ZPUino (http://www.alvie.com/zpuino) you can have as many serial ports as you wish (however you might need to reduce UART receive fifo, if not enough memory on FPGA).

Álvaro

[Reply #7 on:]

and zpuino maybe even procurable some day? I don't see any place to order.
Think I will go simpler route for now: max3100 in dip package, add one for each extra serial port needed.
Only 8 word FIFO, need to write some code I guess.

[Reply #8 on:]

Think I will go simpler route for now: max3100 in dip package, add one for each extra serial port needed.
Only 8 word FIFO, need to write some code I guess.

My only problem is how expensive these are.  I know you can get samples, but did you see the price is $8 each (qty 1), and you have to buy over 100 to get the price less than $5 each?

I'm tempted to simply add an ATMEGA168 (price each $3.33 at qty 1) for the ultimate "extra" UART. 

With, as you note, a bit of coding.

Just a thought.

Brad.

[Reply #9 on:]

Geez, how does Maxim expect to sell things?
Yeah, those are expensive.

[Reply #10 on:]

Yes i wonder if it were possible that in a future the cheap versions of arduino wuold have a bit more uarts and PWM

[Reply #11 on:]

I wish there was a tiny85/84 equivalent with a UART.

I won't be holding my breath though.

______
Rob

[Reply #12 on:]

If MAXIM can offer a whole ATMega328 with a UART for <$6, why can't  a standalone UART be offered for even less? Makes  you wonder ...

[Reply #13 on:]

If MAXIM can offer a whole ATMega328 with a UART for <$6, why can't  a standalone UART be offered for even less? Makes  you wonder ...

Economies of scale. They can roll out 328s by the thousand and know they'll sell them. A UART adapter is a more niche item, and so have a more niche price tag.

[Reply #14 on:]

Very nice, pity about the package, I'm getting better at soldering SMDs but that might be a problem.

Check out the MAX3110.

-j