From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [RFC 00/24] OMAP serial driver flow control fixes, and preparation for DMA engine conversion Date: Thu, 11 Oct 2012 09:05:22 -0500 Message-ID: <5076D222.5080600@ti.com> References: <20121006123803.GD15246@n2100.arm.linux.org.uk> <507427DA.6020409@ti.com> <87mwzuxjtc.fsf@deeprootsystems.com> <507694CF.3020204@ti.com> <20121011095443.GH28061@n2100.arm.linux.org.uk> <50769D8C.8030401@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <50769D8C.8030401@ti.com> Sender: linux-omap-owner@vger.kernel.org To: Sourav Cc: Russell King - ARM Linux , Kevin Hilman , Greg Kroah-Hartman , Tony Lindgren , linux-serial@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Alan Cox List-Id: linux-serial@vger.kernel.org Hi Sourav, On 10/11/2012 05:21 AM, Sourav wrote: [snip] > I already enable software flow control and did the testing on beagle, > where things are working fine > after off mode. > But if I enable hardware flow control, the teraterm does not allow me to > load my fs and uImage from mmc. > If you have any pointers on how to test hardware flow control, I will > like to do that on my beagle board. For h/w flow control, you need to check if the CTS and RTS signals are being brought out to the serial header on the beagle-board. Looking at the schematics for the 3430 beagle board, it appears that only the UART RX and TX signals are available on the serial header. Therefore, I don't believe you can test h/w flow control using the console with that board. I do see that you can access all the UART2 signals (RX/TX/CTS/RTS) via the expansion connector on the beagle. However, to connect to a serial port on a PC you need to have a voltage level-shifter in-between. There are some companies out there that make them [1], but you need to make sure you have one that can support a 1.8V input. Cheers Jon [1] http://elinux.org/RS232_Level_Shifter