From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B8B58CCF2C9 for ; Sun, 18 Oct 2026 19:11:27 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1xIWHO-0002Xf-Rk; Sun, 18 Oct 2026 15:10:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xIWHM-0002XX-To for qemu-devel@nongnu.org; Sun, 18 Oct 2026 15:10:44 -0400 Received: from sonata.ens-lyon.org ([140.77.166.138]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xIWHL-0005MV-6F for qemu-devel@nongnu.org; Sun, 18 Oct 2026 15:10:44 -0400 Received: from localhost (localhost [127.0.0.1]) by sonata.ens-lyon.org (Postfix) with ESMTP id 8F0CDA224F; Sun, 18 Oct 2026 21:10:40 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ens-lyon.org; s=dkim; t=1792350640; bh=tI7taOf2WllFIMxt0qDY8jf+bzzAgKREIKKq+JtGEsA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=m78U9z8b/iQH340n0zrmyI7IIrl/wRP3yXRSVeP2aGHS39xUAxa3GDBgWgaH7ngXh uWwWi0CuKZxnIUIJb8jOB+IpKl5U1IxbNblrOnnnwymPhK/5rU9BzCXQqistbhgV+X 1BR4EcfAmfscT9+yNXQvnyNQT/oesuBl5m8LyFVD7LzHj+5aA5SQ1iU38FK13RCAXB 5mu1cs6ZMGvM/odjDSG3Dg11M/7C99DmNwRXATI0K6ekqjwOkJdsDC2tBuaqowrJFl 0bb9HwEQ8qpJ8Sk6zFT6vAUEVGGZpwfuw5TDKszytQxi0ckxVjit4YWI8aPNtphLAQ Z1TgcyUDqTZbw== Received: from sonata.ens-lyon.org ([127.0.0.1]) by localhost (sonata.ens-lyon.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id LF3-CjjQ4zMg; Sun, 18 Oct 2026 21:10:40 +0200 (CEST) Received: from end (lfbn-bor-1-980-210.w90-120.abo.wanadoo.fr [90.120.173.210]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by sonata.ens-lyon.org (Postfix) with ESMTPSA id 5EBB7A1C00; Sun, 18 Oct 2026 21:10:40 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ens-lyon.org; s=dkim; t=1792350640; bh=tI7taOf2WllFIMxt0qDY8jf+bzzAgKREIKKq+JtGEsA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=m78U9z8b/iQH340n0zrmyI7IIrl/wRP3yXRSVeP2aGHS39xUAxa3GDBgWgaH7ngXh uWwWi0CuKZxnIUIJb8jOB+IpKl5U1IxbNblrOnnnwymPhK/5rU9BzCXQqistbhgV+X 1BR4EcfAmfscT9+yNXQvnyNQT/oesuBl5m8LyFVD7LzHj+5aA5SQ1iU38FK13RCAXB 5mu1cs6ZMGvM/odjDSG3Dg11M/7C99DmNwRXATI0K6ekqjwOkJdsDC2tBuaqowrJFl 0bb9HwEQ8qpJ8Sk6zFT6vAUEVGGZpwfuw5TDKszytQxi0ckxVjit4YWI8aPNtphLAQ Z1TgcyUDqTZbw== Received: from samy by end with local (Exim 4.100.1) (envelope-from ) id 1xIWHH-00000002Af3-3y0B; Sun, 18 Oct 2026 21:10:39 +0200 Date: Sun, 18 Oct 2026 21:10:39 +0200 From: Samuel Thibault To: Alexander Epaneshnikov Cc: qemu-devel@nongnu.org, brltty@brltty.app Subject: Re: baum: NVDA does not detect usb-braille Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: I am not organized Received-SPF: pass client-ip=140.77.166.138; envelope-from=SRS0=U7TD=II=ens-lyon.org=samuel.thibault@bounce.ens-lyon.org; helo=sonata.ens-lyon.org X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org (splitting the actually-unrelated questions) Alexander Epaneshnikov, le dim. 18 oct. 2026 21:52:44 +0300, a ecrit: > On Sun, Oct 18, 2026 at 06:26:53PM +0200, Samuel Thibault wrote: > > Ah, that is a requirement of the protocol? Then we need to do that > > indeed. What is the value of the uint8_t protocol field when it > > expects to receive 0x01 and 0x84? > > It is 1 (on). For serial displays, NVDA's Baum driver > (source/brailleDisplayDrivers/baum.py) first sends 0x15 with 0 to make > sure the protocol is off, then sends 0x15 with 1 twice, "in case the > display misses the first one". After that it waits for the cell count > and the device identity. According to the comment in that driver, a > real display answers only when the protocol goes from off to on. On > that transition it sends its device identity, its serial number and > its cell count, and it sends nothing if the protocol was already on. > NVDA itself only waits for the cell count and the identity. Does the device sends the cell count first or the device identity first? Samuel