/* * paperclip64sc.c - Paperclip 64sc joyport dongle emulation. * * Written by * Marco van den Heuvel * Roberto Muscedere * * This file is part of VICE, the Versatile Commodore Emulator. * See README for copyright notice. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA * 02111-1307 USA. * */ #include "vice.h" #include #include #include #include "joyport.h" #include "paperclip64sc.h" #include "resources.h" #include "snapshot.h" /* Control port <--> paperclip64sc connections: cport | paperclip64sc | I/O ---------------------------- 1 | PROM O0 | I 2 | PROM O1 | I 3 | COUNTER CLK | O 4 | COUNTER CLR | O 6 | PROM CE | O 7 | +5VDC | Power 8 | GND | Ground Works on: - native joystick port(s) (x64/x64sc/xscpu64/x128) */ /* Paperclip64SC (Spell-Check) Dongle description: This emulation works only for the "paperclip64d-sc", and "paperclip64e-sc" files. Other versions require different dongles (ie. "paperclip64d", "paperclip64e" are different). Documentation/information used for making the emulation: https://c64preservation.com/index.php/bbs/dm.php?thread=1579 The current emulation does the following: 1- wait for the bit 4, 3 and 2 of the joystick port to become xxx000xx 2- wait for the bit 4, 3 and 2 of the joystick port to become xxx010xx 3- wait for the bit 4, 3 and 2 of the joystick port to become xxx111xx 4- wait for the bit 4, 3 and 2 of the joystick port to become xxx010xx 5- set the first bit-pair of the key on bits 1 and 0 of the joystick port. The key sequence is : 02 00 00 01 03 02 01 03 02 01 02 01 02 01 02 00 01 02 00 01 03 03 02 00 00 00 00 00 00 00 01 03 03 02 00 01 02 00 01 02 01 02 01 02 01 03 02 01 03 02 00 00 01 03 03 03 03 03 03 03 03 03 03 03 After setting the first bits of the sequence the following needs to happen before setting the next bit: 1- wait for the bit 4, 3 and 2 of the joystick port to become xxx111xx 2- wait for the bit 4, 3 and 2 of the joystick port to become xxx010xx Be aware that the current emulation keeps the 'old' bits set between steps 1 and 2. The "key" sequence is found below in the code; it has 64 values. */ static int paperclip64sc_enabled[JOYPORT_MAX_PORTS] = {0}; static int counter[JOYPORT_MAX_PORTS] = {0}; static uint8_t command[JOYPORT_MAX_PORTS] = {0xff}; static uint8_t output_enable[JOYPORT_MAX_PORTS] = {0}; static const uint8_t keys[64] = { 0, 1, 0, 3, 1, 1, 2, 1, 2, 0, 2, 2, 0, 3, 0, 3, 2, 1, 0, 0, 1, 0, 3, 2, 3, 3, 1, 1, 2, 3, 3, 1, 3, 1, 2, 3, 1, 2, 3, 1, 1, 1, 2, 3, 1, 2, 2, 2, 1, 0, 0, 2, 0, 1, 3, 2, 2, 0, 1, 0, 1, 2, 3, 2 }; /* ------------------------------------------------------------------------- */ static int joyport_paperclip64sc_set_enabled(int port, int enabled) { int new_state = enabled ? 1 : 0; if (new_state == paperclip64sc_enabled[port]) { return 0; } if (new_state) { /* enabled, set command to 0 */ command[port] = 0; } /* set current state */ paperclip64sc_enabled[port] = new_state; return 0; } static uint8_t paperclip64sc_read(int port) { uint8_t retval = 0xff; if (output_enable[port]) { /* if the output is enabled, return current key bits */ retval &= (keys[counter[port]] | 0xfc); } return retval; } static void paperclip64sc_store(int port, uint8_t val) { uint8_t new_command = val & 0x1c; uint8_t reset; uint8_t clk; uint8_t old_clk; if (new_command == command[port]) { return; } output_enable[port] = !(val & JOYPORT_FIRE); /* output enable line is on joyport 'fire' pin */ reset = !(val & 8); if (reset) { /* reset line asserted, set counter to 0 */ counter[port] = 0; } else { clk = val & JOYPORT_LEFT; /* clock line is on joyport 'left' pin */ old_clk = command[port] & JOYPORT_LEFT; if (old_clk && !clk) { /* clock line asserted, increment key position */ counter[port]++; if (counter[port] == 64) { counter[port] = 0; } } } command[port] = new_command; } static void paperclip64sc_powerup(int port) { /* reset counter */ counter[port] = 0; } /* ------------------------------------------------------------------------- */ /* Some prototypes are needed */ static int paperclip64sc_write_snapshot(struct snapshot_s *s, int port); static int paperclip64sc_read_snapshot(struct snapshot_s *s, int port); static joyport_t joyport_paperclip64sc_device = { "Dongle (Paperclip64SC)", /* name of the device */ JOYPORT_RES_ID_NONE, /* device can be used in multiple ports at the same time */ JOYPORT_IS_NOT_LIGHTPEN, /* device is NOT a lightpen */ JOYPORT_POT_OPTIONAL, /* device does NOT use the potentiometer lines */ JOYPORT_5VDC_REQUIRED, /* device NEEDS +5VDC to work */ JOYSTICK_ADAPTER_ID_NONE, /* device is NOT a joystick adapter */ JOYPORT_DEVICE_C64_DONGLE, /* device is a C64 Dongle */ 0x1C, /* bits 4, 3 and 2 are output bits */ joyport_paperclip64sc_set_enabled,/* device enable/disable function */ paperclip64sc_read, /* digital line read function */ paperclip64sc_store, /* digital line store function */ NULL, /* NO pot-x read function */ NULL, /* NO pot-y read function */ paperclip64sc_powerup, /* powerup function */ paperclip64sc_write_snapshot, /* device write snapshot function */ paperclip64sc_read_snapshot, /* device read snapshot function */ NULL, /* NO device hook function */ 0 /* NO device hook function mask */ }; /* ------------------------------------------------------------------------- */ int joyport_paperclip64sc_resources_init(void) { return joyport_device_register(JOYPORT_ID_PAPERCLIP64SC, &joyport_paperclip64sc_device); } /* ------------------------------------------------------------------------- */ /* PAPERCLIP64SC snapshot module format: type | name | description ----------------------------- DWORD | counter | counter BYTE | command | command BYTE | state | state */ static const char snap_module_name[] = "PAPERCLIP64SC"; #define SNAP_MAJOR 0 #define SNAP_MINOR 1 static int paperclip64sc_write_snapshot(struct snapshot_s *s, int port) { snapshot_module_t *m; m = snapshot_module_create(s, snap_module_name, SNAP_MAJOR, SNAP_MINOR); if (m == NULL) { return -1; } if (0 || SMW_DW(m, (uint32_t)counter[port]) < 0 || SMW_B(m, command[port]) < 0) { snapshot_module_close(m); return -1; } return snapshot_module_close(m); } static int paperclip64sc_read_snapshot(struct snapshot_s *s, int port) { uint8_t major_version, minor_version; snapshot_module_t *m; m = snapshot_module_open(s, snap_module_name, &major_version, &minor_version); if (m == NULL) { return -1; } /* Do not accept versions higher than current */ if (snapshot_version_is_bigger(major_version, minor_version, SNAP_MAJOR, SNAP_MINOR)) { snapshot_set_error(SNAPSHOT_MODULE_HIGHER_VERSION); goto fail; } if (0 || SMR_DW_INT(m, &counter[port]) < 0 || SMR_B(m, &command[port]) < 0) { goto fail; } return snapshot_module_close(m); fail: snapshot_module_close(m); return -1; }