{ "content": [ { "type": "text", "text": "# mouse(4) (man)\n\n**Summary:** mouse - serial mouse interface\n\n## See Also\n\n- ttyS(4)\n- gpm(8)\n\n## Section Outline\n\n- **NAME** (2 lines)\n- **CONFIGURATION** (2 lines)\n- **DESCRIPTION** (1 lines) — 7 subsections\n - Introduction (29 lines)\n - Microsoft protocol (9 lines)\n - 3-button Microsoft protocol (5 lines)\n - Logitech protocol (6 lines)\n - Mousesystems protocol (14 lines)\n - Sun protocol (3 lines)\n - MM protocol (10 lines)\n- **FILES** (3 lines)\n- **SEE ALSO** (2 lines)\n- **COLOPHON** (7 lines)\n\n## Full Content\n\n### NAME\n\nmouse - serial mouse interface\n\n### CONFIGURATION\n\nSerial mice are connected to a serial RS232/V24 dialout line, see ttyS(4) for a description.\n\n### DESCRIPTION\n\n#### Introduction\n\nThe pinout of the usual 9 pin plug as used for serial mice is:\n\npin name used for\n2 RX Data\n3 TX -12 V, Imax = 10 mA\n4 DTR +12 V, Imax = 10 mA\n7 RTS +12 V, Imax = 10 mA\n5 GND Ground\n\nThis is the specification, in fact 9 V suffices with most mice.\n\nThe mouse driver can recognize a mouse by dropping RTS to low and raising it again. About 14\nms later the mouse will send 0x4D ('M') on the data line. After a further 63 ms, a Micro‐\nsoft-compatible 3-button mouse will send 0x33 ('3').\n\nThe relative mouse movement is sent as dx (positive means right) and dy (positive means\ndown). Various mice can operate at different speeds. To select speeds, cycle through the\nspeeds 9600, 4800, 2400, and 1200 bit/s, each time writing the two characters from the table\nbelow and waiting 0.1 seconds. The following table shows available speeds and the strings\nthat select them:\n\nbit/s string\n9600 *q\n4800 *p\n2400 *o\n1200 *n\n\nThe first byte of a data packet can be used for synchronization purposes.\n\n#### Microsoft protocol\n\nThe Microsoft protocol uses 1 start bit, 7 data bits, no parity and one stop bit at the speed\nof 1200 bits/sec. Data is sent to RxD in 3-byte packets. The dx and dy movements are sent\nas two's-complement, lb (rb) are set when the left (right) button is pressed:\n\nbyte d6 d5 d4 d3 d2 d1 d0\n1 1 lb rb dy7 dy6 dx7 dx6\n2 0 dx5 dx4 dx3 dx2 dx1 dx0\n3 0 dy5 dy4 dy3 dy2 dy1 dy0\n\n#### 3-button Microsoft protocol\n\nOriginal Microsoft mice only have two buttons. However, there are some three button mice\nwhich also use the Microsoft protocol. Pressing or releasing the middle button is reported\nby sending a packet with zero movement and no buttons pressed. (Thus, unlike for the other\ntwo buttons, the status of the middle button is not reported in each packet.)\n\n#### Logitech protocol\n\nLogitech serial 3-button mice use a different extension of the Microsoft protocol: when the\nmiddle button is up, the above 3-byte packet is sent. When the middle button is down a\n4-byte packet is sent, where the 4th byte has value 0x20 (or at least has the 0x20 bit set).\nIn particular, a press of the middle button is reported as 0,0,0,0x20 when no other buttons\nare down.\n\n#### Mousesystems protocol\n\nThe Mousesystems protocol uses 1 start bit, 8 data bits, no parity and two stop bits at the\nspeed of 1200 bits/sec. Data is sent to RxD in 5-byte packets. dx is sent as the sum of the\ntwo two's-complement values, dy is send as negated sum of the two two's-complement values.\nlb (mb, rb) are cleared when the left (middle, right) button is pressed:\n\nbyte d7 d6 d5 d4 d3 d2 d1 d0\n1 1 0 0 0 0 lb mb rb\n2 0 dxa6 dxa5 dxa4 dxa3 dxa2 dxa1 dxa0\n3 0 dya6 dya5 dya4 dya3 dya2 dya1 dya0\n4 0 dxb6 dxb5 dxb4 dxb3 dxb2 dxb1 dxb0\n5 0 dyb6 dyb5 dyb4 dyb3 dyb2 dyb1 dyb0\n\nBytes 4 and 5 describe the change that occurred since bytes 2 and 3 were transmitted.\n\n#### Sun protocol\n\nThe Sun protocol is the 3-byte version of the above 5-byte Mousesystems protocol: the last\ntwo bytes are not sent.\n\n#### MM protocol\n\nThe MM protocol uses 1 start bit, 8 data bits, odd parity and one stop bit at the speed of\n1200 bits/sec. Data is sent to RxD in 3-byte packets. dx and dy are sent as single signed\nvalues, the sign bit indicating a negative value. lb (mb, rb) are set when the left (middle,\nright) button is pressed:\n\nbyte d7 d6 d5 d4 d3 d2 d1 d0\n1 1 0 0 dxs dys lb mb rb\n2 0 dx6 dx5 dx4 dx3 dx2 dx1 dx0\n3 0 dy6 dy5 dy4 dy3 dy2 dy1 dy0\n\n### FILES\n\n/dev/mouse\nA commonly used symbolic link pointing to a mouse device.\n\n### SEE ALSO\n\nttyS(4), gpm(8)\n\n### COLOPHON\n\nThis page is part of release 5.10 of the Linux man-pages project. A description of the\nproject, information about reporting bugs, and the latest version of this page, can be found\nat https://www.kernel.org/doc/man-pages/.\n\n\n\nLinux 2020-08-13 MOUSE(4)\n\n" } ], "structuredContent": { "command": "mouse", "section": "4", "mode": "man", "summary": "mouse - serial mouse interface", "synopsis": null, "flags": [], "examples": [], "see_also": [ { "name": "ttyS", "section": "4", "url": "https://www.chedong.com/phpMan.php/man/ttyS/4/json" }, { "name": "gpm", "section": "8", "url": "https://www.chedong.com/phpMan.php/man/gpm/8/json" } ], "section_outline": [ { "name": "NAME", "lines": 2, "subsections": [] }, { "name": "CONFIGURATION", "lines": 2, "subsections": [] }, { "name": "DESCRIPTION", "lines": 1, "subsections": [ { "name": "Introduction", "lines": 29 }, { "name": "Microsoft protocol", "lines": 9 }, { "name": "3-button Microsoft protocol", "lines": 5 }, { "name": "Logitech protocol", "lines": 6 }, { "name": "Mousesystems protocol", "lines": 14 }, { "name": "Sun protocol", "lines": 3 }, { "name": "MM protocol", "lines": 10 } ] }, { "name": "FILES", "lines": 3, "subsections": [] }, { "name": "SEE ALSO", "lines": 2, "subsections": [] }, { "name": "COLOPHON", "lines": 7, "subsections": [] } ] } }