2 Copyright 2019,2020 Jun Wako <wakojun@gmail.com>
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>.
29 #include "ibmpc_usb.h"
33 static void matrix_make(uint8_t code);
34 static void matrix_break(uint8_t code);
36 static int8_t process_cs1(uint8_t code);
37 static int8_t process_cs2(uint8_t code);
38 static int8_t process_cs3(uint8_t code);
41 static uint8_t matrix[MATRIX_ROWS];
42 #define ROW(code) ((code>>3)&0x0F)
43 #define COL(code) (code&0x07)
45 static int16_t read_wait(uint16_t wait_ms)
47 uint16_t start = timer_read();
49 while ((code = ibmpc_host_recv()) == -1 && timer_elapsed(start) < wait_ms);
53 static uint16_t read_keyboard_id(void)
59 //code = ibmpc_host_send(0xF5);
62 code = ibmpc_host_send(0xF2);
63 if (code == -1) { id = 0xFFFF; goto DONE; } // XT or No keyboard
64 if (code != 0xFA) { id = 0xFFFE; goto DONE; } // Broken PS/2?
66 // ID takes 500ms max TechRef [8] 4-41
67 code = read_wait(500);
68 if (code == -1) { id = 0x0000; goto DONE; } // AT
69 id = (code & 0xFF)<<8;
71 // Mouse responds with one-byte 00, this returns 00FF [y] p.14
72 code = read_wait(500);
77 //code = ibmpc_host_send(0xF4);
82 void hook_early_init(void)
88 void matrix_init(void)
92 // initialize matrix state: all keys off
93 for (uint8_t i=0; i < MATRIX_ROWS; i++) matrix[i] = 0x00;
99 * keyboard recognition
101 * 1. Send F2 to get keyboard ID
102 * a. no ACK(FA): XT keyobard
103 * b. ACK but no ID: 84-key AT keyboard CodeSet2
104 * c. ID is AB 83: PS/2 keyboard CodeSet2
105 * d. ID is BF BF: Terminal keyboard CodeSet3
106 * e. error on recv: maybe broken PS/2
108 uint8_t current_protocol = 0;
109 uint16_t keyboard_id = 0x0000;
110 keyboard_kind_t keyboard_kind = NONE;
111 uint8_t matrix_scan(void)
113 // scan code reading states
126 static uint16_t init_time;
130 xprintf("\nERR:%02X\n", ibmpc_error);
132 // when recv error, neither send error nor buffer full
133 if (!(ibmpc_error & (IBMPC_ERR_SEND | IBMPC_ERR_FULL))) {
134 // keyboard init again
141 // clear or process error
142 ibmpc_error = IBMPC_ERR_NONE;
145 // check ISR state debug
146 if (ibmpc_isr_debug) {
147 xprintf("\nISR:%04X\n", ibmpc_isr_debug);
151 // check protocol AT/XT
152 if (ibmpc_protocol != current_protocol) {
153 xprintf("\nPROTO:%02X\n", ibmpc_protocol);
154 current_protocol = ibmpc_protocol;
159 xprintf("I%u ", timer_read());
160 keyboard_kind = NONE;
161 keyboard_id = 0x0000;
169 // Reset XT-initialize keyboard
170 // XT: hard reset 500ms for IBM XT Type-1 keyboard and clones
171 // XT: soft reset 20ms min(clock Lo)
172 ibmpc_host_disable(); // soft reset: inihibit(clock Lo/Data Hi)
173 IBMPC_RST_LO(); // hard reset: reset pin Lo
175 init_time = timer_read();
176 state = XT_RESET_WAIT;
179 if (timer_elapsed(init_time) > 500) {
180 state = XT_RESET_DONE;
184 IBMPC_RST_HIZ(); // hard reset: reset pin HiZ
185 ibmpc_host_isr_clear();
186 ibmpc_host_enable(); // soft reset: idle(clock Hi/Data Hi)
188 xprintf("X%u ", timer_read());
189 init_time = timer_read();
193 // 1) Read BAT code and ID on keybaord power-up
194 // For example, XT/AT sends 'AA' and Terminal sends 'AA BF BF' after BAT
195 // AT 84-key: POR and BAT can take 900-9900ms according to AT TechRef [8] 4-7
196 // AT 101/102-key: POR and BAT can take 450-2500ms according to AT TechRef [8] 4-39
197 // 2) Read key typed by user or anything after error on protocol or scan code
198 // This can happen in case of keyboard hotswap, unstable hardware, signal integrity problem or bug
200 /* wait until keyboard sends any code without 10000ms timeout
201 if (timer_elapsed(init_time) > 10000) {
205 if (ibmpc_host_recv() != -1) { // wait for AA
206 xprintf("W%u ", timer_read());
207 init_time = timer_read();
212 // NOTE: we can omit to wait BF BF
213 // ID takes 500ms max? TechRef [8] 4-41, though 1ms is enough for 122-key Terminal 6110345
214 if (timer_elapsed(init_time) > 500) {
217 if (ibmpc_host_recv() != -1) { // wait for BF
218 xprintf("W%u ", timer_read());
219 init_time = timer_read();
224 if (timer_elapsed(init_time) > 500) {
227 if (ibmpc_host_recv() != -1) { // wait for BF
228 xprintf("W%u ", timer_read());
233 xprintf("R%u ", timer_read());
235 // SKIDATA-2-DE(and some other keyboards?) stores 'Code Set' setting in nonvlatile memory
236 // and keeps it until receiving reset. Sending reset here may be useful to clear it, perhaps.
237 // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#select-alternate-scan-codesf0
238 //ibmpc_host_send(0xFF); // reset command
239 //read_wait(500); // BAT takes 600-900ms(84-key) or 300-500ms(101/102-key) [8] 4-7, 4-39
241 keyboard_id = read_keyboard_id();
243 xprintf("\nERR:%02X\n", ibmpc_error);
244 ibmpc_error = IBMPC_ERR_NONE;
247 if (0x0000 == keyboard_id) { // CodeSet2 AT(IBM PC AT 84-key)
248 keyboard_kind = PC_AT;
249 } else if (0xFFFF == keyboard_id) { // CodeSet1 XT
250 keyboard_kind = PC_XT;
251 } else if (0xFFFE == keyboard_id) { // CodeSet2 PS/2 fails to response?
252 keyboard_kind = PC_AT;
253 } else if (0x00FF == keyboard_id) { // Mouse is not supported
254 xprintf("Mouse: not supported\n");
255 keyboard_kind = NONE;
256 #ifdef G80_2551_SUPPORT
257 } else if (0xAB86 == keyboard_id ||
258 0xAB85 == keyboard_id) { // For G80-2551 and other 122-key terminal
259 // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#ab86
260 // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#ab85
262 if ((0xFA == ibmpc_host_send(0xF0)) &&
263 (0xFA == ibmpc_host_send(0x03))) {
264 // switch to code set 3
265 keyboard_kind = PC_TERMINAL;
267 keyboard_kind = PC_AT;
270 } else if (0xBFB0 == keyboard_id) { // IBM RT Keyboard
271 // https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#bfb0
272 // TODO: LED indicator fix
273 //keyboard_kind = PC_TERMINAL_IBM_RT;
274 keyboard_kind = PC_TERMINAL;
275 } else if (0xAB00 == (keyboard_id & 0xFF00)) { // CodeSet2 PS/2
276 keyboard_kind = PC_AT;
277 } else if (0xBF00 == (keyboard_id & 0xFF00)) { // CodeSet3 Terminal
278 keyboard_kind = PC_TERMINAL;
280 keyboard_kind = PC_AT;
283 xprintf("ID:%04X(%d)\n", keyboard_id, keyboard_kind);
288 xprintf("S%u ", timer_read());
289 switch (keyboard_kind) {
293 led_set(host_keyboard_leds());
296 // Set all keys to make/break type
297 ibmpc_host_send(0xF8);
303 xprintf("L%u ", timer_read());
306 uint16_t code = ibmpc_host_recv();
312 // Keyboard Error/Overrun([3]p.26) or Buffer full
313 // Scan Code Set 1: 0xFF
314 // Scan Code Set 2 and 3: 0x00
315 // Buffer full(IBMPC_ERR_FULL): 0xFF
316 if (code == 0x00 || code == 0xFF) {
317 xprintf("\n!OVERRUN![");
319 // read and ignore data
322 } while ((code = ibmpc_host_recv()) != -1);
331 switch (keyboard_kind) {
333 if (process_cs1(code) == -1) state = INIT;
336 if (process_cs2(code) == -1) state = INIT;
339 if (process_cs3(code) == -1) state = INIT;
353 bool matrix_is_on(uint8_t row, uint8_t col)
355 return (matrix[row] & (1<<col));
359 uint8_t matrix_get_row(uint8_t row)
364 uint8_t matrix_key_count(void)
367 for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
368 count += bitpop(matrix[i]);
375 static void matrix_make(uint8_t code)
377 if (!matrix_is_on(ROW(code), COL(code))) {
378 matrix[ROW(code)] |= 1<<COL(code);
383 static void matrix_break(uint8_t code)
385 if (matrix_is_on(ROW(code), COL(code))) {
386 matrix[ROW(code)] &= ~(1<<COL(code));
390 void matrix_clear(void)
392 for (uint8_t i=0; i < MATRIX_ROWS; i++) matrix[i] = 0x00;
395 void led_set(uint8_t usb_led)
397 if (keyboard_kind == NONE) return;
398 //if (keyboard_kind != PC_AT) return;
400 uint8_t ibmpc_led = 0;
401 if (usb_led & (1<<USB_LED_SCROLL_LOCK))
402 ibmpc_led |= (1<<IBMPC_LED_SCROLL_LOCK);
403 if (usb_led & (1<<USB_LED_NUM_LOCK))
404 ibmpc_led |= (1<<IBMPC_LED_NUM_LOCK);
405 if (usb_led & (1<<USB_LED_CAPS_LOCK))
406 ibmpc_led |= (1<<IBMPC_LED_CAPS_LOCK);
407 ibmpc_host_set_led(ibmpc_led);
411 /*******************************************************************************
412 * XT: Scan Code Set 1
416 * E0-escaped scan codes are translated into unused range of the matrix.(54-7F)
418 * 01-53: Normal codes used in original XT keyboard
419 * 54-7F: Not used in original XT keyboard
421 * 0 1 2 3 4 5 6 7 8 9 A B C D E F
422 * 50 - - - - * * x x x x * * * * * *
423 * 60 * * * * x x x x x x x x x x x *
424 * 70 x * * x * * x * * x * x * x x *
426 * -: codes existed in original XT keyboard
427 * *: E0-escaped codes translated
428 * x: Non-espcaped codes(Some are not used in real keyboards probably)
430 * Codes assigned in range 54-7F:
432 * 50 - 60 Up* 70 KANAx
433 * 51 - 61 Left* 71 Insert*
434 * 52 - 62 Down* 72 Delete*
435 * 53 - 63 Right* 73 ROx
436 * 54 PrintScr* 64 F13x 74 Home*
437 * 55 Pause* 65 F14x 75 End*
438 * 56 Euro2x 66 F15x 76 F24x
439 * 57 F11x 67 F16x 77 PageUp*
440 * 58 F12x 68 F17x 78 PageDown*
441 * 59 Keypad=x 69 F18x 79 HENKANx
442 * 5A LGUI* 6A F19x 7A RCTL*
443 * 5B RGUI* 6B F20x 7B MUHENKANx
444 * 5C APP* 6C F21x 7C RALT*
445 * 5D Mute* 6D F22x 7D JPYx
446 * 5E Volume Down* 6E F23x 7E Keypad,x
447 * 5F Volume Up* 6F Keypad Enter* 7F Keypad/ *
449 static uint8_t cs1_e0code(uint8_t code) {
451 // Original IBM XT keyboard doesn't use E0-codes probably
452 // Some XT compatilble keyobards need these keys?
453 case 0x37: return 0x54; // Print Screen
454 case 0x46: return 0x55; // Ctrl + Pause
455 case 0x5B: return 0x5A; // Left GUI
456 case 0x5C: return 0x5B; // Right GUI
457 case 0x5D: return 0x5C; // Application
458 case 0x20: return 0x5D; // Mute
459 case 0x2E: return 0x5E; // Volume Down
460 case 0x30: return 0x5F; // Volume Up
461 case 0x48: return 0x60; // Up
462 case 0x4B: return 0x61; // Left
463 case 0x50: return 0x62; // Down
464 case 0x4D: return 0x63; // Right
465 case 0x1C: return 0x6F; // Keypad Enter
466 case 0x52: return 0x71; // Insert
467 case 0x53: return 0x72; // Delete
468 case 0x47: return 0x74; // Home
469 case 0x4F: return 0x75; // End
470 case 0x49: return 0x77; // Page Up
471 case 0x51: return 0x78; // Page Down
472 case 0x1D: return 0x7A; // Right Ctrl
473 case 0x38: return 0x7C; // Right Alt
474 case 0x35: return 0x7F; // Keypad /
476 // Shared matrix cell with other keys
477 case 0x5E: return 0x70; // Power (KANA)
478 case 0x5F: return 0x79; // Sleep (HENKAN)
479 case 0x63: return 0x7B; // Wake (MUHENKAN)
482 xprintf("!CS1_E0_%02X!\n", code);
488 static int8_t process_cs1(uint8_t code)
493 // Pause: E1 1D 45, E1 9D C5 [a] (TODO: test)
499 // Check invalid codes; 0x59-7F won't be used in real XT keyboards probably
500 // 0x62 is used to handle escape code E0 and E1
501 if ((code & 0x7F) >= 0x62) {
502 xprintf("!CS1_INV!\n");
520 matrix_break(code & 0x7F);
535 matrix_make(cs1_e0code(code));
537 matrix_break(cs1_e0code(code & 0x7F));
582 /*******************************************************************************
583 * AT, PS/2: Scan Code Set 2
585 * Exceptional Handling
586 * --------------------
587 * Some keys should be handled exceptionally. See [b].
589 * Scan codes are varied or prefix/postfix'd depending on modifier key state.
591 * 1) Insert, Delete, Home, End, PageUp, PageDown, Up, Down, Right, Left
592 * a) when Num Lock is off
593 * modifiers | make | break
594 * ----------+---------------------------+----------------------
595 * Ohter | <make> | <break>
596 * LShift | E0 F0 12 <make> | <break> E0 12
597 * RShift | E0 F0 59 <make> | <break> E0 59
598 * L+RShift | E0 F0 12 E0 F0 59 <make> | <break> E0 59 E0 12
600 * b) when Num Lock is on
601 * modifiers | make | break
602 * ----------+---------------------------+----------------------
603 * Other | E0 12 <make> | <break> E0 F0 12
604 * Shift'd | <make> | <break>
606 * Handling: These prefix/postfix codes are ignored.
610 * modifiers | make | break
611 * ----------+---------------------------+----------------------
612 * Ohter | <make> | <break>
613 * LShift | E0 F0 12 <make> | <break> E0 12
614 * RShift | E0 F0 59 <make> | <break> E0 59
615 * L+RShift | E0 F0 12 E0 F0 59 <make> | <break> E0 59 E0 12
617 * Handling: These prefix/postfix codes are ignored.
621 * modifiers | make | break
622 * ----------+--------------+-----------------------------------
623 * Other | E0 12 E0 7C | E0 F0 7C E0 F0 12
624 * Shift'd | E0 7C | E0 F0 7C
625 * Control'd | E0 7C | E0 F0 7C
628 * Handling: These prefix/postfix codes are ignored, and both scan codes
629 * 'E0 7C' and 84 are seen as PrintScreen.
632 * modifiers | make(no break code)
633 * ----------+--------------------------------------------------
634 * Other | E1 14 77 E1 F0 14 F0 77
635 * Control'd | E0 7E E0 F0 7E
637 * Handling: Both code sequences are treated as a whole.
638 * And we need a ad hoc 'pseudo break code' hack to get the key off
639 * because it has no break code.
642 * 'Hanguel/English'(F1) and 'Hanja'(F2) have no break code. See [a].
643 * These two Korean keys need exceptional handling and are not supported for now.
646 static uint8_t cs2_e0code(uint8_t code) {
648 // E0 prefixed codes translation See [a].
649 case 0x11: return 0x0F; // right alt
650 case 0x14: return 0x17; // right control
651 case 0x1F: return 0x19; // left GUI
652 case 0x27: return 0x1F; // right GUI
653 case 0x2F: return 0x5C; // apps
654 case 0x4A: return 0x60; // keypad /
655 case 0x5A: return 0x62; // keypad enter
656 case 0x69: return 0x27; // end
657 case 0x6B: return 0x53; // cursor left
658 case 0x6C: return 0x2F; // home
659 case 0x70: return 0x39; // insert
660 case 0x71: return 0x37; // delete
661 case 0x72: return 0x3F; // cursor down
662 case 0x74: return 0x47; // cursor right
663 case 0x75: return 0x4F; // cursor up
664 case 0x7A: return 0x56; // page down
665 case 0x7D: return 0x5E; // page up
666 case 0x7C: return 0x7F; // Print Screen
667 case 0x7E: return 0x00; // Control'd Pause
669 case 0x21: return 0x65; // volume down
670 case 0x32: return 0x6E; // volume up
671 case 0x23: return 0x6F; // mute
672 case 0x10: return 0x08; // (WWW search) -> F13
673 case 0x18: return 0x10; // (WWW favourites) -> F14
674 case 0x20: return 0x18; // (WWW refresh) -> F15
675 case 0x28: return 0x20; // (WWW stop) -> F16
676 case 0x30: return 0x28; // (WWW forward) -> F17
677 case 0x38: return 0x30; // (WWW back) -> F18
678 case 0x3A: return 0x38; // (WWW home) -> F19
679 case 0x40: return 0x40; // (my computer) -> F20
680 case 0x48: return 0x48; // (email) -> F21
681 case 0x2B: return 0x50; // (calculator) -> F22
682 case 0x34: return 0x08; // (play/pause) -> F13
683 case 0x3B: return 0x10; // (stop) -> F14
684 case 0x15: return 0x18; // (previous track) -> F15
685 case 0x4D: return 0x20; // (next track) -> F16
686 case 0x50: return 0x28; // (media select) -> F17
687 case 0x5E: return 0x50; // (ACPI wake) -> F22
688 case 0x3F: return 0x57; // (ACPI sleep) -> F23
689 case 0x37: return 0x5F; // (ACPI power) -> F24
691 // https://github.com/tmk/tmk_keyboard/pull/636
692 case 0x03: return 0x18; // Help DEC LK411 -> F15
693 case 0x04: return 0x08; // F13 DEC LK411
694 case 0x0B: return 0x20; // Do DEC LK411 -> F16
695 case 0x0C: return 0x10; // F14 DEC LK411
696 case 0x0D: return 0x19; // LCompose DEC LK411 -> LGUI
697 case 0x79: return 0x6D; // KP- DEC LK411 -> PCMM
698 case 0x83: return 0x28; // F17 DEC LK411
699 default: return (code & 0x7F);
703 static int8_t process_cs2(uint8_t code)
705 // scan code reading states
735 case 0x84: // Alt'd PrintScreen
739 case 0xAA: // Self-test passed
740 case 0xFC: // Self-test failed
741 // reset or plugin-in new keyboard
745 default: // normal key make
751 xprintf("!CS2_INIT!\n");
756 case E0: // E0-Prefixed
758 case 0x12: // to be ignored
759 case 0x59: // to be ignored
768 matrix_make(cs2_e0code(code));
771 xprintf("!CS2_E0!\n");
776 case F0: // Break code
782 case 0x84: // Alt'd PrintScreen
792 xprintf("!CS2_F0!\n");
797 case E0_F0: // Break code of E0-prefixed
799 case 0x12: // to be ignored
800 case 0x59: // to be ignored
806 matrix_break(cs2_e0code(code));
809 xprintf("!CS2_E0_F0!\n");
814 // Pause make: E1 14 77
837 // Pause break: E1 F0 14 F0 77
873 * Terminal: Scan Code Set 3
876 * https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#scan-code-set-3
878 static int8_t process_cs3(uint8_t code)
883 #ifdef G80_2551_SUPPORT
884 // G80-2551 four extra keys around cursor keys
896 case 0x83: // PrintScreen
899 case 0x84: // Keypad *
902 case 0x85: // Muhenkan
908 case 0x87: // Hiragana
911 case 0x8B: // Left GUI
914 case 0x8C: // Right GUI
917 case 0x8D: // Application
920 #ifdef G80_2551_SUPPORT
921 case 0x80: // G80-2551 four extra keys around cursor keys
925 default: // normal key make
929 xprintf("!CS3_READY!\n");
934 case F0: // Break code
936 case 0x83: // PrintScreen
940 case 0x84: // Keypad *
944 case 0x85: // Muhenkan
952 case 0x87: // Hiragana
956 case 0x8B: // Left GUI
960 case 0x8C: // Right GUI
964 case 0x8D: // Application
973 xprintf("!CS3_F0!\n");
978 #ifdef G80_2551_SUPPORT
980 * G80-2551 terminal keyboard support
981 * https://deskthority.net/wiki/Cherry_G80-2551
982 * https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-AT-Keyboard-Protocol#g80-2551-in-code-set-3
984 case G80: // G80-2551 four extra keys around cursor keys
986 case (0x26): // TD= -> JYEN
989 case (0x25): // page with edge -> NUHS
992 case (0x16): // two pages -> RO
995 case (0x1E): // calc -> KANA
1010 case (0x26): // TD= -> JYEN
1013 case (0x25): // page with edge -> NUHS
1016 case (0x16): // two pages -> RO
1019 case (0x1E): // calc -> KANA
1035 * IBM PC Keyboard Protocol Resources:
1037 * [a] Microsoft USB HID to PS/2 Translation Table - Scan Code Set 1 and 2
1038 * http://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/translate.pdf
1040 * [b] Microsoft Keyboard Scan Code Specification - Special rules of Scan Code Set 1 and 2
1041 * http://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/scancode.doc
1043 * [1] PS/2 Reference Manuals - Collection of IBM Personal System/2 documents.
1044 * http://www.mcamafia.de/pdf/pdfref.htm
1046 * [2] Keyboard and Auxiliary Device Controller - Signal Timing and Format
1047 * http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
1049 * [3] Keyboards(101- and 102-key) - Keyboard Layout, Scan Code Set, POR, and Commands.
1050 * http://www.mcamafia.de/pdf/ibm_hitrc11.pdf
1052 * [4] IBM PC XT Keyboard Protocol
1053 * https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-XT-Keyboard-Protocol
1055 * [5] IBM Keyboard Scan Code by John Elliott - 83-key, 84-key, 102-key and 122-key
1056 * https://www.seasip.info/VintagePC/index.html
1058 * [6] IBM 1391406 Keyboard - Scan Code Set 2 of 102-key PS/2 keyboard
1059 * https://www.seasip.info/VintagePC/ibm_1391406.html
1061 * [7] The IBM 6110344 Keyboard - Scan Code Set 3 of 122-key terminal keyboard
1062 * https://www.seasip.info/VintagePC/ibm_6110344.html
1064 * [8] IBM PC AT Technical Reference 1986
1065 * http://bitsavers.org/pdf/ibm/pc/at/6183355_PC_AT_Technical_Reference_Mar86.pdf
1067 * [y] TrackPoint Engineering Specifications for version 3E
1068 * https://web.archive.org/web/20100526161812/http://wwwcssrv.almaden.ibm.com/trackpoint/download.html
1070 * [z] [Soarer's XT/AT/PS2/Terminal to USB converter]
1071 * https://geekhack.org/index.php?topic=17458.0