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Serial card for i7 Mac?

CJ_Miller

Well-known member
Can anybody recommend one? Not USB, nor serial ATA... but a regular serial card. RS232 or RS422. If it works in 10.6 and Vista is a big plus. Can be PCI or PCIe.

I am finding a glut of Windoze serial cards, but when I search for Mac serial I get random nonsense. Thanks!

 

CJ_Miller

Well-known member
I just realized that I gave myself away here, PCI slot indicates that this is not a real Mac. I have many real Macs but this box is a placeholder for an intel Mac I cannot (even close to) afford yet.

But the question still stands. I hear very little about serial cards for Mac, but sifting through the info has turned up a few things. Also, I am hoping to use it for MIDI, so I guess I have a struggle here. My AMT8 under Logic is ok, but I tend to prefer real serial MIDI and it is foolish if this cannot be done, I will try. If I find a card that is viable, maybe a MIDI driver will need to be written.

I have read that these work in Mac, but they list no drivers on their site:

http://us.startech.com/product/PEX2S5531P-2S1P-Port-PCI-Express-Parallel-Serial-Combo-Card-with-16550-UART

 

Anonymous Freak

Well-known member
In OS X, a serial port is a serial port is a serial port. PCI, "native", USB, whatever.

On my "Hack Pro", OS X recognizes the built-in serial ports on my motherboard just fine as cu.serial1 and cu.serial2. Likewise, a USB serial adapter shows up just fine as well. Since RS-232 serial tops out at 1/10th the speed of USB 1.1's SLOW speed, there is no reason to insist on a PCI card rather than a USB adapter.

Also, check your motherboard to see if you have an onboard serial header. While it may not have a serial port on the back panel, it may have a 9-pin header, so all you would need is a simple $5 internal adapter.

 

CJ_Miller

Well-known member
In OS X, a serial port is a serial port is a serial port. PCI, "native", USB, whatever. On my "Hack Pro", OS X recognizes the built-in serial ports on my motherboard just fine as cu.serial1 and cu.serial2.
It is true that so long as there are drivers, one is assured of some serial functionality... But Macs have always been funny when it comes to routing services with serial communications. For instance, why are most 3rd party adaptors incompatible with LocalTalk? It is still RS422, right? And then there are MIDI managers, such as OMS and CoreMIDI - they do not automatically assume that a serial port is legit for MIDI I/O. They typically require a MIDI driver. Some 3rd party drivers might work for other adaptors, while others might not.

A more pressing reason for my question was to find out what serial chipsets have built-in MacOS drivers. If it is the same as the RS232 ports in an Xserve then it should definitely work. But if it is some random serial card with no drivers, it would not be of any use at all.

Likewise, a USB serial adapter shows up just fine as well. Since RS-232 serial tops out at 1/10th the speed of USB 1.1's SLOW speed, there is no reason to insist on a PCI card rather than a USB adapter.
I am not looking for raw data dumping speed, but rather precise timing. USB, like ethernet, often waits and packetizes blocks of data and sends them at "convenient" times. Whereas a real serial port can send and receive bits in real time. For tight MIDI timing it can be handy to avoid any additional levels of translation or abstraction which can be heard as it sends data. Keep in mind that USB was developed and pushed because it is cheaper, and better for dumping large files to and from appliances such as cameras and MP3 players. It was not meant for real time communication.

Also, check your motherboard to see if you have an onboard serial header. While it may not have a serial port on the back panel, it may have a 9-pin header, so all you would need is a simple $5 internal adapter.
Excellent advice! The connector often is the most expensive part, and cheap manufacturers will frequently omit them while the functionality lies hidden on the board.

 
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