/* * wordcraft-dongle.c - tape port dongle that helps WordCraft work. * * Written by * Olaf 'Rhialto' Seibert * based on public information from http://bitbarn.co.uk/trusley/early_days.htm * http://bitbarn.co.uk/dryfire/dcpe.php#pets * * 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 "cmdline.h" #include "log.h" #include "maincpu.h" #include "machine.h" #include "mem.h" #include "resources.h" #include "tapeport.h" #include "wordcraft-dongle.h" static int wordcraft_dongle_enabled[TAPEPORT_MAX_PORTS] = { 0 }; static log_t wclog = LOG_DEFAULT; /* ------------------------------------------------------------------------- */ /* Some prototypes are needed */ static void wordcraft_dongle_powerup(int port); static int wordcraft_dongle_enable(int port, int val); static void wordcraft_dongle_set_motor_line(int port, int value); static void wordcraft_dongle_toggle_write_line(int port, int value); static void wordcraft_dongle_set_sense_line(int port, int value); static void wordcraft_dongle_set_read_line(int port, int value); static tapeport_device_t wordcraft_dongle_device = { "Wordcraft dongle", /* device name */ TAPEPORT_DEVICE_TYPE_DONGLE, /* device is a 'dongle' type device */ VICE_MACHINE_PET, /* device works on PETs only */ TAPEPORT_PORT_ALL_MASK, /* device works on all ports */ wordcraft_dongle_enable, /* device enable function */ wordcraft_dongle_powerup, /* device specific hard reset function */ NULL, /* NO device shutdown function */ wordcraft_dongle_set_motor_line, /* set motor line function */ wordcraft_dongle_toggle_write_line, /* set write line function */ wordcraft_dongle_set_sense_line, /* set sense line function */ wordcraft_dongle_set_read_line, /* set read line function */ NULL, /* NO device snapshot write function */ NULL /* NO device snapshot read function */ }; /* ------------------------------------------------------------------------- */ struct dongle_data { bool load_line; bool clock_in_line; bool data_in_line; bool clock_enable_line; bool value_detected; int shift_count; unsigned int dongle_value; } dongle_data[TAPEPORT_MAX_PORTS]; static unsigned int reverse16(unsigned int bits) { unsigned int v = bits; /* swap odd and even bits */ v = ((v >> 1) & 0x5555) | ((v & 0x5555) << 1); /* swap consecutive pairs */ v = ((v >> 2) & 0x3333) | ((v & 0x3333) << 2); /* swap nibbles ... */ v = ((v >> 4) & 0x0F0F) | ((v & 0x0F0F) << 4); /* swap bytes */ v = ((v >> 8) & 0x00FF) | ((v & 0x00FF) << 8); return v; } static int wordcraft_dongle_enable(int port, int value) { int val = value ? 1 : 0; if (wordcraft_dongle_enabled[port] == val) { return 0; } wordcraft_dongle_enabled[port] = val; if (!val) { dongle_data[port].value_detected = false; } dongle_data[port].dongle_value = reverse16(0xD210); /* $084B or 2123. Most common value */ /* dongle_data[port].dongle_value = reverse16(0x4800); / * 7 bits used */ /* dongle_data[port].dongle_value = reverse16(0x2C00); / * 7 bits used */ /* dongle_data[port].dongle_value = reverse16(0x0200); / * 7 bits used */ /* * Working values: * Wordcraft * E10 reverse(0x0200) (7 bits used) * /F10 reverse(0x9000) some copies crash later * 80me /F32 reverse(0xD210) * 80e /G21 reverse(0x4800) s/n D25210 (7 bits used) * 80me /G25 reverse(0x2C00) (7 bits used) * 80 /H12 reverse(0xD210) (15 bits used) doesn't set sense line? * 96xxxx/H12 reverse(0xD210) (15 bits used) * 80 /H17 reverse(0xD210) * 96xxxx/H17 reverse(0xD210) (15 bits used) * CBM 80F3 80ME distributor code D /F32: reverse(D210) (7 bits used) * * M=matrix, otherwise letter quality printers? * E=english? * FR=french AZ=azerty * GB=english QW=qwerty * NL=dutch * 80 = 80 cols, 32 KB * 96 = 80 cols, 96 KB * * Loading documents: g,filename,drivenr,chapternr * for NL version: l,filename,drivenr,chapternr * u,$ directory listing */ return 0; } int wordcraft_dongle_resources_init(int amount) { wclog = log_open("WordCraft"); return tapeport_device_register(TAPEPORT_DEVICE_WORDCRAFT_DONGLE, &wordcraft_dongle_device); } /* ---------------------------------------------------------------------*/ static void wordcraft_dongle_detect_values(int port) { /* Try to detect the expected dongle value(s) by inspecting the code */ if (!dongle_data[port].value_detected) { /* Look at PC */ uint16_t pc = reg_pc; /* unfortunately maincpu_get_pc(); returns 0 */ unsigned int i; uint8_t lo = 0, hi = 0; bool lo_found = false; uint8_t *mem = mem_ram; log_message(wclog, "Detecting WordCraft dongle code from PC = $%04x", pc); if (pc >= 0x8000) { log_error(wclog, "PC too high for WordCraft dongle code. Ignoring."); return; } /* Search for the sequence LDY $7D STY $xxxx TYA EOR #hi */ for (i = 0; i < 128; i++) { if (mem[pc + i + 0x00] == 0xA4 && /* LDY $7D */ mem[pc + i + 0x01] == 0x7D && mem[pc + i + 0x02] == 0x8C && /* STY $xxxx */ mem[pc + i + 0x05] == 0x98 && /* TYA */ mem[pc + i + 0x06] == 0x49) { /* EOR #hi */ hi = mem[pc + i + 0x07]; if (mem[pc + i + 0x08] == 0xD0 && /* BNE */ mem[pc + i + 0x0C] == 0x49) { /* EOR #lo */ lo = mem[pc + i + 0x0D]; lo_found = true; } if (lo_found) { log_message(wclog, "Found $%02x $%02x at $%04x +$%02x and +$%02x", hi, lo, pc, i+0x07, i+0x0D); } else { log_message(wclog, "Found $%02x at $%04x +$%02x", hi, pc, i+0x07); } break; } } if (i >= 128) { log_error(wclog, "Did NOT find expected dongle code/value near %04x", pc); /* Try for version /D3 */ i = 0x7E; /* 0x2735 - 0x26b7 */ if (mem[pc + i + 0] == 0x98 && /* TYA */ mem[pc + i + 1] == 0x49) { /* EOR $hi */ hi = mem[pc + i + 2]; log_message(wclog, "Found %02x 2nd try at %04x", hi, pc + i + 2); } } if (lo_found ? hi|lo : hi) { dongle_data[port].value_detected = true; dongle_data[port].dongle_value = reverse16((hi << 8) | lo); } else { /* The "WMAST?0ME/F32" program accepts any value except 0 */ log_message(wclog, "Value zero found; not using that."); } } } /* ---------------------------------------------------------------------*/ static void wordcraft_dongle_powerup(int port) { dongle_data[port].shift_count = 0; } static void wordcraft_dongle_set_motor_line(int port, int value) { if (value != dongle_data[port].clock_enable_line) { log_verbose(wclog, "wordcraft_dongle_set_motor_line: %d %d", port, value); } dongle_data[port].clock_enable_line = value; /* but apparently not used */ } /* * The tape input on the PET is strictly edge-triggered. To compensate for that, * after every "active transition", the dongle checking code toggles the active * direction. This way it can detect both 1 and 0 inputs. * Because of this, we do not need to worry if we send duplicate "transitions" * in the same direction into the PIA code. Those are implemented inaccurately. */ static void wordcraft_dongle_toggle_write_line(int port, int value) { log_debug(wclog, "wordcraft_dongle_toggle_write_line: %d %d", port, value); if (!dongle_data[port].clock_in_line && value) { /* * Shift a bit on the RISING edge of the clock. The dongle checking * code does both transitions right after each other, before reading * input. So it doesn't really matter which edge is used. LSB first. */ bool bit = (dongle_data[port].dongle_value >> dongle_data[port].shift_count) & 1; log_verbose(wclog, "wordcraft_dongle_toggle_write_line: send bit #%d %d", dongle_data[port].shift_count, bit); dongle_data[port].shift_count++; tapeport_set_read_in(bit, port); dongle_data[port].data_in_line = bit; } dongle_data[port].clock_in_line = value; } static void wordcraft_dongle_set_sense_line(int port, int value) { if (!dongle_data[port].load_line && value) { log_verbose(wclog, "wordcraft_dongle_sense_line: %d %d rise: restart shift sequence", port, value); /* Restart the shifting sequence */ dongle_data[port].shift_count = 0; wordcraft_dongle_detect_values(port); } dongle_data[port].load_line = value; } static void wordcraft_dongle_set_read_line(int port, int value) { log_debug(wclog, "wordcraft_dongle_set_read_line: %d %d", port, value); }