RE: [Bluez-devel] CF cards capable of 1Mbps?
From: Halam Rose <hidden>
Date: 2003-09-09 13:47:52
1 Mbps is the bulk data rate but there are overheads so only 723Kbps is possible with any Bluetooth link. Halam -----Original Message----- From: David Woodhouse [mailto:dwmw2@infradead.org] Sent: 09 September 2003 13:48 To: Nils Faerber Cc: bluez-devel@lists.sourceforge.net Subject: Re: [Bluez-devel] CF cards capable of 1Mbps? On Tue, 2003-09-09 at 14:20 +0200, Nils Faerber wrote:
The fact that the UART of the CF card sais it would run at 115kbps does not at all mean that the actual data throughput is only 115kbps. For example we have a Brainboxes CF card which you set to 115kbps but actually uses 1Mbps between the UART and the CSR chipset then. The UART clock is simply higher so that a devider for 115kbps results in 1Mbps. Only if your OS tries to setup something based on the baudrate you would be in trouble here. Linux has no problems with the extra bitrate.
This is true. Which is why I confirmed with BNEP bandwidth tests that I only get about 9-10Kbps transfer rate, and checked what speed the CSR chip thinks it's talking at too... # pskey -d /dev/tts/0 -b Physical device :/dev/tts/0 Speed :115200 Use BCSP :YES Initiating read thread BT SYS: Initializing BCSP BT SYS: BCSP initialized and syncronized Synchronized Successfully read firmware info. Firmware version: 272 pskey>191 Key 0191 length 10 01d8 0006 00fa 0014 0004 0000 0004 001e 0064 000a The information about the Brainboxes card is appreciated -- thanks. http://www.brainboxes.com/products/bluetooth/product.asp?id=BL-565 says only 721Kbps, but that'll do me fine; I'll see if I can find one of those for slightly less than the insane amount of money they seem to claim is the recommended price. I had a Cyberblue BLUE-CF01 which had a baud_base of 1152000, but the first one went back due to radio-side reliability problems -- only about 1 in 5 times would it detect and correctly get name from my phone which was sitting right next to it. The second one was better for a while, but then started to lose RX characters, until last week it finally gave up completely and I don't receive _anything_ from the CSR chip. I don't think I want another of those :) -- dwmw2 ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Bluez-devel mailing list Bluez-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-devel ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Bluez-devel mailing list Bluez-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-devel