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diff --git a/Documentation/input/devices/atarikbd.rst b/Documentation/input/devices/atarikbd.rst new file mode 100644 index 0000000000..0c4c7804cc --- /dev/null +++ b/Documentation/input/devices/atarikbd.rst @@ -0,0 +1,820 @@ +==================================== +Intelligent Keyboard (ikbd) Protocol +==================================== + + +Introduction +============ + +The Atari Corp. Intelligent Keyboard (ikbd) is a general purpose keyboard +controller that is flexible enough that it can be used in a variety of +products without modification. The keyboard, with its microcontroller, +provides a convenient connection point for a mouse and switch-type joysticks. +The ikbd processor also maintains a time-of-day clock with one second +resolution. +The ikbd has been designed to be general enough that it can be used with a +variety of new computer products. Product variations in a number of +keyswitches, mouse resolution, etc. can be accommodated. +The ikbd communicates with the main processor over a high speed bi-directional +serial interface. It can function in a variety of modes to facilitate +different applications of the keyboard, joysticks, or mouse. Limited use of +the controller is possible in applications in which only a unidirectional +communications medium is available by carefully designing the default modes. + +Keyboard +======== + +The keyboard always returns key make/break scan codes. The ikbd generates +keyboard scan codes for each key press and release. The key scan make (key +closure) codes start at 1, and are defined in Appendix A. For example, the +ISO key position in the scan code table should exist even if no keyswitch +exists in that position on a particular keyboard. The break code for each key +is obtained by ORing 0x80 with the make code. + +The special codes 0xF6 through 0xFF are reserved for use as follows: + +=================== ==================================================== + Code Command +=================== ==================================================== + 0xF6 status report + 0xF7 absolute mouse position record + 0xF8-0xFB relative mouse position records (lsbs determined by + mouse button states) + 0xFC time-of-day + 0xFD joystick report (both sticks) + 0xFE joystick 0 event + 0xFF joystick 1 event +=================== ==================================================== + +The two shift keys return different scan codes in this mode. The ENTER key +and the RETurn key are also distinct. + +Mouse +===== + +The mouse port should be capable of supporting a mouse with resolution of +approximately 200 counts (phase changes or 'clicks') per inch of travel. The +mouse should be scanned at a rate that will permit accurate tracking at +velocities up to 10 inches per second. +The ikbd can report mouse motion in three distinctly different ways. It can +report relative motion, absolute motion in a coordinate system maintained +within the ikbd, or by converting mouse motion into keyboard cursor control +key equivalents. +The mouse buttons can be treated as part of the mouse or as additional +keyboard keys. + +Relative Position Reporting +--------------------------- + +In relative position mode, the ikbd will return relative mouse position +records whenever a mouse event occurs. A mouse event consists of a mouse +button being pressed or released, or motion in either axis exceeding a +settable threshold of motion. Regardless of the threshold, all bits of +resolution are returned to the host computer. +Note that the ikbd may return mouse relative position reports with +significantly more than the threshold delta x or y. This may happen since no +relative mouse motion events will be generated: (a) while the keyboard has +been 'paused' ( the event will be stored until keyboard communications is +resumed) (b) while any event is being transmitted. + +The relative mouse position record is a three byte record of the form +(regardless of keyboard mode):: + + %111110xy ; mouse position record flag + ; where y is the right button state + ; and x is the left button state + X ; delta x as twos complement integer + Y ; delta y as twos complement integer + +Note that the value of the button state bits should be valid even if the +MOUSE BUTTON ACTION has set the buttons to act like part of the keyboard. +If the accumulated motion before the report packet is generated exceeds the ++127...-128 range, the motion is broken into multiple packets. +Note that the sign of the delta y reported is a function of the Y origin +selected. + +Absolute Position reporting +--------------------------- + +The ikbd can also maintain absolute mouse position. Commands exist for +resetting the mouse position, setting X/Y scaling, and interrogating the +current mouse position. + +Mouse Cursor Key Mode +--------------------- + +The ikbd can translate mouse motion into the equivalent cursor keystrokes. +The number of mouse clicks per keystroke is independently programmable in +each axis. The ikbd internally maintains mouse motion information to the +highest resolution available, and merely generates a pair of cursor key events +for each multiple of the scale factor. +Mouse motion produces the cursor key make code immediately followed by the +break code for the appropriate cursor key. The mouse buttons produce scan +codes above those normally assigned for the largest envisioned keyboard (i.e. +LEFT=0x74 & RIGHT=0x75). + +Joystick +======== + +Joystick Event Reporting +------------------------ + +In this mode, the ikbd generates a record whenever the joystick position is +changed (i.e. for each opening or closing of a joystick switch or trigger). + +The joystick event record is two bytes of the form:: + + %1111111x ; Joystick event marker + ; where x is Joystick 0 or 1 + %x000yyyy ; where yyyy is the stick position + ; and x is the trigger + +Joystick Interrogation +---------------------- + +The current state of the joystick ports may be interrogated at any time in +this mode by sending an 'Interrogate Joystick' command to the ikbd. + +The ikbd response to joystick interrogation is a three byte report of the form:: + + 0xFD ; joystick report header + %x000yyyy ; Joystick 0 + %x000yyyy ; Joystick 1 + ; where x is the trigger + ; and yyy is the stick position + +Joystick Monitoring +------------------- + +A mode is available that devotes nearly all of the keyboard communications +time to reporting the state of the joystick ports at a user specifiable rate. +It remains in this mode until reset or commanded into another mode. The PAUSE +command in this mode not only stop the output but also temporarily stops +scanning the joysticks (samples are not queued). + +Fire Button Monitoring +---------------------- + +A mode is provided to permit monitoring a single input bit at a high rate. In +this mode the ikbd monitors the state of the Joystick 1 fire button at the +maximum rate permitted by the serial communication channel. The data is packed +8 bits per byte for transmission to the host. The ikbd remains in this mode +until reset or commanded into another mode. The PAUSE command in this mode not +only stops the output but also temporarily stops scanning the button (samples +are not queued). + +Joystick Key Code Mode +---------------------- + +The ikbd may be commanded to translate the use of either joystick into the +equivalent cursor control keystroke(s). The ikbd provides a single breakpoint +velocity joystick cursor. +Joystick events produce the make code, immediately followed by the break code +for the appropriate cursor motion keys. The trigger or fire buttons of the +joysticks produce pseudo key scan codes above those used by the largest key +matrix envisioned (i.e. JOYSTICK0=0x74, JOYSTICK1=0x75). + +Time-of-Day Clock +================= + +The ikbd also maintains a time-of-day clock for the system. Commands are +available to set and interrogate the timer-of-day clock. Time-keeping is +maintained down to a resolution of one second. + +Status Inquiries +================ + +The current state of ikbd modes and parameters may be found by sending status +inquiry commands that correspond to the ikbd set commands. + +Power-Up Mode +============= + +The keyboard controller will perform a simple self-test on power-up to detect +major controller faults (ROM checksum and RAM test) and such things as stuck +keys. Any keys down at power-up are presumed to be stuck, and their BREAK +(sic) code is returned (which without the preceding MAKE code is a flag for a +keyboard error). If the controller self-test completes without error, the code +0xF0 is returned. (This code will be used to indicate the version/release of +the ikbd controller. The first release of the ikbd is version 0xF0, should +there be a second release it will be 0xF1, and so on.) +The ikbd defaults to a mouse position reporting with threshold of 1 unit in +either axis and the Y=0 origin at the top of the screen, and joystick event +reporting mode for joystick 1, with both buttons being logically assigned to +the mouse. After any joystick command, the ikbd assumes that joysticks are +connected to both Joystick0 and Joystick1. Any mouse command (except MOUSE +DISABLE) then causes port 0 to again be scanned as if it were a mouse, and +both buttons are logically connected to it. If a mouse disable command is +received while port 0 is presumed to be a mouse, the button is logically +assigned to Joystick1 (until the mouse is reenabled by another mouse command). + +ikbd Command Set +================ + +This section contains a list of commands that can be sent to the ikbd. Command +codes (such as 0x00) which are not specified should perform no operation +(NOPs). + +RESET +----- + +:: + + 0x80 + 0x01 + +N.B. The RESET command is the only two byte command understood by the ikbd. +Any byte following an 0x80 command byte other than 0x01 is ignored (and causes +the 0x80 to be ignored). +A reset may also be caused by sending a break lasting at least 200mS to the +ikbd. +Executing the RESET command returns the keyboard to its default (power-up) +mode and parameter settings. It does not affect the time-of-day clock. +The RESET command or function causes the ikbd to perform a simple self-test. +If the test is successful, the ikbd will send the code of 0xF0 within 300mS +of receipt of the RESET command (or the end of the break, or power-up). The +ikbd will then scan the key matrix for any stuck (closed) keys. Any keys found +closed will cause the break scan code to be generated (the break code arriving +without being preceded by the make code is a flag for a key matrix error). + +SET MOUSE BUTTON ACTION +----------------------- + +:: + + 0x07 + %00000mss ; mouse button action + ; (m is presumed = 1 when in MOUSE KEYCODE mode) + ; mss=0xy, mouse button press or release causes mouse + ; position report + ; where y=1, mouse key press causes absolute report + ; and x=1, mouse key release causes absolute report + ; mss=100, mouse buttons act like keys + +This command sets how the ikbd should treat the buttons on the mouse. The +default mouse button action mode is %00000000, the buttons are treated as part +of the mouse logically. +When buttons act like keys, LEFT=0x74 & RIGHT=0x75. + +SET RELATIVE MOUSE POSITION REPORTING +------------------------------------- + +:: + + 0x08 + +Set relative mouse position reporting. (DEFAULT) Mouse position packets are +generated asynchronously by the ikbd whenever motion exceeds the setable +threshold in either axis (see SET MOUSE THRESHOLD). Depending upon the mouse +key mode, mouse position reports may also be generated when either mouse +button is pressed or released. Otherwise the mouse buttons behave as if they +were keyboard keys. + +SET ABSOLUTE MOUSE POSITIONING +------------------------------ + +:: + + 0x09 + XMSB ; X maximum (in scaled mouse clicks) + XLSB + YMSB ; Y maximum (in scaled mouse clicks) + YLSB + +Set absolute mouse position maintenance. Resets the ikbd maintained X and Y +coordinates. +In this mode, the value of the internally maintained coordinates does NOT wrap +between 0 and large positive numbers. Excess motion below 0 is ignored. The +command sets the maximum positive value that can be attained in the scaled +coordinate system. Motion beyond that value is also ignored. + +SET MOUSE KEYCODE MODE +---------------------- + +:: + + 0x0A + deltax ; distance in X clicks to return (LEFT) or (RIGHT) + deltay ; distance in Y clicks to return (UP) or (DOWN) + +Set mouse monitoring routines to return cursor motion keycodes instead of +either RELATIVE or ABSOLUTE motion records. The ikbd returns the appropriate +cursor keycode after mouse travel exceeding the user specified deltas in +either axis. When the keyboard is in key scan code mode, mouse motion will +cause the make code immediately followed by the break code. Note that this +command is not affected by the mouse motion origin. + +SET MOUSE THRESHOLD +------------------- + +:: + + 0x0B + X ; x threshold in mouse ticks (positive integers) + Y ; y threshold in mouse ticks (positive integers) + +This command sets the threshold before a mouse event is generated. Note that +it does NOT affect the resolution of the data returned to the host. This +command is valid only in RELATIVE MOUSE POSITIONING mode. The thresholds +default to 1 at RESET (or power-up). + +SET MOUSE SCALE +--------------- + +:: + + 0x0C + X ; horizontal mouse ticks per internal X + Y ; vertical mouse ticks per internal Y + +This command sets the scale factor for the ABSOLUTE MOUSE POSITIONING mode. +In this mode, the specified number of mouse phase changes ('clicks') must +occur before the internally maintained coordinate is changed by one +(independently scaled for each axis). Remember that the mouse position +information is available only by interrogating the ikbd in the ABSOLUTE MOUSE +POSITIONING mode unless the ikbd has been commanded to report on button press +or release (see SET MOUSE BUTTON ACTION). + +INTERROGATE MOUSE POSITION +-------------------------- + +:: + + 0x0D + Returns: + 0xF7 ; absolute mouse position header + BUTTONS + 0000dcba ; where a is right button down since last interrogation + ; b is right button up since last + ; c is left button down since last + ; d is left button up since last + XMSB ; X coordinate + XLSB + YMSB ; Y coordinate + YLSB + +The INTERROGATE MOUSE POSITION command is valid when in the ABSOLUTE MOUSE +POSITIONING mode, regardless of the setting of the MOUSE BUTTON ACTION. + +LOAD MOUSE POSITION +------------------- + +:: + + 0x0E + 0x00 ; filler + XMSB ; X coordinate + XLSB ; (in scaled coordinate system) + YMSB ; Y coordinate + YLSB + +This command allows the user to preset the internally maintained absolute +mouse position. + +SET Y=0 AT BOTTOM +----------------- + +:: + + 0x0F + +This command makes the origin of the Y axis to be at the bottom of the +logical coordinate system internal to the ikbd for all relative or absolute +mouse motion. This causes mouse motion toward the user to be negative in sign +and away from the user to be positive. + +SET Y=0 AT TOP +-------------- + +:: + + 0x10 + +Makes the origin of the Y axis to be at the top of the logical coordinate +system within the ikbd for all relative or absolute mouse motion. (DEFAULT) +This causes mouse motion toward the user to be positive in sign and away from +the user to be negative. + +RESUME +------ + +:: + + 0x11 + +Resume sending data to the host. Since any command received by the ikbd after +its output has been paused also causes an implicit RESUME this command can be +thought of as a NO OPERATION command. If this command is received by the ikbd +and it is not PAUSED, it is simply ignored. + +DISABLE MOUSE +------------- + +:: + + 0x12 + +All mouse event reporting is disabled (and scanning may be internally +disabled). Any valid mouse mode command resumes mouse motion monitoring. (The +valid mouse mode commands are SET RELATIVE MOUSE POSITION REPORTING, SET +ABSOLUTE MOUSE POSITIONING, and SET MOUSE KEYCODE MODE. ) +N.B. If the mouse buttons have been commanded to act like keyboard keys, this +command DOES affect their actions. + +PAUSE OUTPUT +------------ + +:: + + 0x13 + +Stop sending data to the host until another valid command is received. Key +matrix activity is still monitored and scan codes or ASCII characters enqueued +(up to the maximum supported by the microcontroller) to be sent when the host +allows the output to be resumed. If in the JOYSTICK EVENT REPORTING mode, +joystick events are also queued. +Mouse motion should be accumulated while the output is paused. If the ikbd is +in RELATIVE MOUSE POSITIONING REPORTING mode, motion is accumulated beyond the +normal threshold limits to produce the minimum number of packets necessary for +transmission when output is resumed. Pressing or releasing either mouse button +causes any accumulated motion to be immediately queued as packets, if the +mouse is in RELATIVE MOUSE POSITION REPORTING mode. +Because of the limitations of the microcontroller memory this command should +be used sparingly, and the output should not be shut of for more than <tbd> +milliseconds at a time. +The output is stopped only at the end of the current 'even'. If the PAUSE +OUTPUT command is received in the middle of a multiple byte report, the packet +will still be transmitted to conclusion and then the PAUSE will take effect. +When the ikbd is in either the JOYSTICK MONITORING mode or the FIRE BUTTON +MONITORING mode, the PAUSE OUTPUT command also temporarily stops the +monitoring process (i.e. the samples are not enqueued for transmission). + +SET JOYSTICK EVENT REPORTING +---------------------------- + +:: + + 0x14 + +Enter JOYSTICK EVENT REPORTING mode (DEFAULT). Each opening or closure of a +joystick switch or trigger causes a joystick event record to be generated. + +SET JOYSTICK INTERROGATION MODE +------------------------------- + +:: + + 0x15 + +Disables JOYSTICK EVENT REPORTING. Host must send individual JOYSTICK +INTERROGATE commands to sense joystick state. + +JOYSTICK INTERROGATE +-------------------- + +:: + + 0x16 + +Return a record indicating the current state of the joysticks. This command +is valid in either the JOYSTICK EVENT REPORTING mode or the JOYSTICK +INTERROGATION MODE. + +SET JOYSTICK MONITORING +----------------------- + +:: + + 0x17 + rate ; time between samples in hundredths of a second + Returns: (in packets of two as long as in mode) + %000000xy ; where y is JOYSTICK1 Fire button + ; and x is JOYSTICK0 Fire button + %nnnnmmmm ; where m is JOYSTICK1 state + ; and n is JOYSTICK0 state + +Sets the ikbd to do nothing but monitor the serial command line, maintain the +time-of-day clock, and monitor the joystick. The rate sets the interval +between joystick samples. +N.B. The user should not set the rate higher than the serial communications +channel will allow the 2 bytes packets to be transmitted. + +SET FIRE BUTTON MONITORING +-------------------------- + +:: + + 0x18 + Returns: (as long as in mode) + %bbbbbbbb ; state of the JOYSTICK1 fire button packed + ; 8 bits per byte, the first sample if the MSB + +Set the ikbd to do nothing but monitor the serial command line, maintain the +time-of-day clock, and monitor the fire button on Joystick 1. The fire button +is scanned at a rate that causes 8 samples to be made in the time it takes for +the previous byte to be sent to the host (i.e. scan rate = 8/10 * baud rate). +The sample interval should be as constant as possible. + +SET JOYSTICK KEYCODE MODE +------------------------- + +:: + + 0x19 + RX ; length of time (in tenths of seconds) until + ; horizontal velocity breakpoint is reached + RY ; length of time (in tenths of seconds) until + ; vertical velocity breakpoint is reached + TX ; length (in tenths of seconds) of joystick closure + ; until horizontal cursor key is generated before RX + ; has elapsed + TY ; length (in tenths of seconds) of joystick closure + ; until vertical cursor key is generated before RY + ; has elapsed + VX ; length (in tenths of seconds) of joystick closure + ; until horizontal cursor keystrokes are generated + ; after RX has elapsed + VY ; length (in tenths of seconds) of joystick closure + ; until vertical cursor keystrokes are generated + ; after RY has elapsed + +In this mode, joystick 0 is scanned in a way that simulates cursor keystrokes. +On initial closure, a keystroke pair (make/break) is generated. Then up to Rn +tenths of seconds later, keystroke pairs are generated every Tn tenths of +seconds. After the Rn breakpoint is reached, keystroke pairs are generated +every Vn tenths of seconds. This provides a velocity (auto-repeat) breakpoint +feature. +Note that by setting RX and/or Ry to zero, the velocity feature can be +disabled. The values of TX and TY then become meaningless, and the generation +of cursor 'keystrokes' is set by VX and VY. + +DISABLE JOYSTICKS +----------------- + +:: + + 0x1A + +Disable the generation of any joystick events (and scanning may be internally +disabled). Any valid joystick mode command resumes joystick monitoring. (The +joystick mode commands are SET JOYSTICK EVENT REPORTING, SET JOYSTICK +INTERROGATION MODE, SET JOYSTICK MONITORING, SET FIRE BUTTON MONITORING, and +SET JOYSTICK KEYCODE MODE.) + +TIME-OF-DAY CLOCK SET +--------------------- + +:: + + 0x1B + YY ; year (2 least significant digits) + MM ; month + DD ; day + hh ; hour + mm ; minute + ss ; second + +All time-of-day data should be sent to the ikbd in packed BCD format. +Any digit that is not a valid BCD digit should be treated as a 'don't care' +and not alter that particular field of the date or time. This permits setting +only some subfields of the time-of-day clock. + +INTERROGATE TIME-OF-DAT CLOCK +----------------------------- + +:: + + 0x1C + Returns: + 0xFC ; time-of-day event header + YY ; year (2 least significant digits) + MM ; month + DD ; day + hh ; hour + mm ; minute + ss ; second + + All time-of-day is sent in packed BCD format. + +MEMORY LOAD +----------- + +:: + + 0x20 + ADRMSB ; address in controller + ADRLSB ; memory to be loaded + NUM ; number of bytes (0-128) + { data } + +This command permits the host to load arbitrary values into the ikbd +controller memory. The time between data bytes must be less than 20ms. + +MEMORY READ +----------- + +:: + + 0x21 + ADRMSB ; address in controller + ADRLSB ; memory to be read + Returns: + 0xF6 ; status header + 0x20 ; memory access + { data } ; 6 data bytes starting at ADR + +This command permits the host to read from the ikbd controller memory. + +CONTROLLER EXECUTE +------------------ + +:: + + 0x22 + ADRMSB ; address of subroutine in + ADRLSB ; controller memory to be called + +This command allows the host to command the execution of a subroutine in the +ikbd controller memory. + +STATUS INQUIRIES +---------------- + +:: + + Status commands are formed by inclusively ORing 0x80 with the + relevant SET command. + + Example: + 0x88 (or 0x89 or 0x8A) ; request mouse mode + Returns: + 0xF6 ; status response header + mode ; 0x08 is RELATIVE + ; 0x09 is ABSOLUTE + ; 0x0A is KEYCODE + param1 ; 0 is RELATIVE + ; XMSB maximum if ABSOLUTE + ; DELTA X is KEYCODE + param2 ; 0 is RELATIVE + ; YMSB maximum if ABSOLUTE + ; DELTA Y is KEYCODE + param3 ; 0 if RELATIVE + ; or KEYCODE + ; YMSB is ABSOLUTE + param4 ; 0 if RELATIVE + ; or KEYCODE + ; YLSB is ABSOLUTE + 0 ; pad + 0 + +The STATUS INQUIRY commands request the ikbd to return either the current mode +or the parameters associated with a given command. All status reports are +padded to form 8 byte long return packets. The responses to the status +requests are designed so that the host may store them away (after stripping +off the status report header byte) and later send them back as commands to +ikbd to restore its state. The 0 pad bytes will be treated as NOPs by the +ikbd. + + Valid STATUS INQUIRY commands are:: + + 0x87 mouse button action + 0x88 mouse mode + 0x89 + 0x8A + 0x8B mnouse threshold + 0x8C mouse scale + 0x8F mouse vertical coordinates + 0x90 ( returns 0x0F Y=0 at bottom + 0x10 Y=0 at top ) + 0x92 mouse enable/disable + ( returns 0x00 enabled) + 0x12 disabled ) + 0x94 joystick mode + 0x95 + 0x96 + 0x9A joystick enable/disable + ( returns 0x00 enabled + 0x1A disabled ) + +It is the (host) programmer's responsibility to have only one unanswered +inquiry in process at a time. +STATUS INQUIRY commands are not valid if the ikbd is in JOYSTICK MONITORING +mode or FIRE BUTTON MONITORING mode. + + +SCAN CODES +========== + +The key scan codes returned by the ikbd are chosen to simplify the +implementation of GSX. + +GSX Standard Keyboard Mapping + +======= ============ +Hex Keytop +======= ============ +01 Esc +02 1 +03 2 +04 3 +05 4 +06 5 +07 6 +08 7 +09 8 +0A 9 +0B 0 +0C \- +0D \= +0E BS +0F TAB +10 Q +11 W +12 E +13 R +14 T +15 Y +16 U +17 I +18 O +19 P +1A [ +1B ] +1C RET +1D CTRL +1E A +1F S +20 D +21 F +22 G +23 H +24 J +25 K +26 L +27 ; +28 ' +29 \` +2A (LEFT) SHIFT +2B \\ +2C Z +2D X +2E C +2F V +30 B +31 N +32 M +33 , +34 . +35 / +36 (RIGHT) SHIFT +37 { NOT USED } +38 ALT +39 SPACE BAR +3A CAPS LOCK +3B F1 +3C F2 +3D F3 +3E F4 +3F F5 +40 F6 +41 F7 +42 F8 +43 F9 +44 F10 +45 { NOT USED } +46 { NOT USED } +47 HOME +48 UP ARROW +49 { NOT USED } +4A KEYPAD - +4B LEFT ARROW +4C { NOT USED } +4D RIGHT ARROW +4E KEYPAD + +4F { NOT USED } +50 DOWN ARROW +51 { NOT USED } +52 INSERT +53 DEL +54 { NOT USED } +5F { NOT USED } +60 ISO KEY +61 UNDO +62 HELP +63 KEYPAD ( +64 KEYPAD / +65 KEYPAD * +66 KEYPAD * +67 KEYPAD 7 +68 KEYPAD 8 +69 KEYPAD 9 +6A KEYPAD 4 +6B KEYPAD 5 +6C KEYPAD 6 +6D KEYPAD 1 +6E KEYPAD 2 +6F KEYPAD 3 +70 KEYPAD 0 +71 KEYPAD . +72 KEYPAD ENTER +======= ============ |