Honda Beat(PP1) ROM mod tool

ecu_mod.py

from minmaxcheck import MinMaxCheck
import sys
import struct
import matplotlib
import numpy as np
from mpl_toolkits.mplot3d import Axes3D

matplotlib.use('TKagg')

import matplotlib.pyplot as plt
from matplotlib import cm
from bullet import Bullet
from minmaxcheck import MinMaxCheck

'''
スピードリミット値計算メモ:
スピードリミット値が小さくなるほどリミッターが発動する速度が上がるようなので、スピードリミット値は車速パルスの周期に対応するものと想定される。
仮にスピードリミット値を車速パルスが4発(駆動軸1回転分？)入るまでを100[us]単位で表した時間として考えてみる。

純正スピードリミット値(約140km/hでリミット): 0x0654 == 1620
1620 * 100[us] = 0.162[s]
1パルスあたり周期は 0.162/4 = 0.0405[s]
周波数に直すと 1/0.0405[s] = 24.7[Hz]
1分間に出力されるパルス数は 24.7 * 60 = 1481.5

60[km/h]のとき637[ppm]でパルスが出力される(JIS D5601)。
1分間に出力されるパルス数を637で割ると、60[km/h]に対する実際の車速の係数が得られるはず。上記数値を当てはめてみると

1481.5 / 637 = 2.33
60[km/h] * 2.33 = 139.8[km/h]


参考文献
    # ref: https://minkara.carview.co.jp/userid/526128/car/457100/2454111/note.aspx
    # ref: https://minkara.carview.co.jp/userid/526128/car/457100/3397385/note.aspx
'''

def bin2speed(b):
    x = struct.unpack('<H', b)[0]
    return (1 / (x / 10000 / 4) * 60 / 637 * 60)

def speed2bin(v):
    x = struct.pack('<H', int(40000 / (v * 637 / 3600)))
    return x[0:2]

class ECUParser:
    def __init__(self, fname):
        self.has_unsaved_value = False
        self.load_ecu_rom(fname=fname)

    def create_fig(self, m, title=''):
        fig = plt.figure()
        fig.canvas.manager.set_window_title(title)
        ax = Axes3D(fig, auto_add_to_figure=False)
        fig.add_axes(ax)
        # ax = fig.add_subplot(111, projection='3d')
        X, Y = np.mgrid[0:17, 0:15]
        na = np.array(m).reshape(17, 15)
        # print(na)
        # X, Y = np.meshgrid(na.shape[0], na.shape[1])
        ax.plot_surface(X, Y, na, rstride=1, cstride=1, cmap=cm.coolwarm)
        ax.set_xlabel('rev')
        ax.set_ylabel('load')
        plt.title(title)
        return plt

    def parse_ecu_rom(self):
        # ref: https://web.archive.org/web/20150516162622/http://www.h3.dion.ne.jp/~beat_ecu/ecu4.html


        self.fi_cut_speed = bin2speed(self.rom_binary[0x0A59:0x0A5B])
        self.fi_restart_speed = bin2speed(self.rom_binary[0x0A61:0x0A63])

        self.load_axis = struct.unpack('<15B', self.rom_binary[0x3C8A:0x3C8A+15])
        self.rev_axis = struct.unpack('<17B', self.rom_binary[0x3C99:0x3C99+17])
        # print(self.load_axis, sum(self.load_axis))
        # print(self.rev_axis, sum(self.rev_axis))

        self.ig_timing_map = []
        for i in range(0x3CA9, 0x3CA9 + 15*17):
            self.ig_timing_map.append(self.rom_binary[i])

        self.th_speed_density_map = []
        for i in range(0x3DC6, 0x3DC6 + 15*17):
            self.th_speed_density_map.append(self.rom_binary[i])

        self.d_jetronic_map = []
        for i in range(0x3EF2, 0x3EF2 + 15*17):
            self.d_jetronic_map.append(self.rom_binary[i])


        # print(ig_timing_map)
        # print(th_speed_density_map)
        # print(d_jetronic_map)

    def load_ecu_rom(self, fname):
        self.has_unsaved_value = False

        self.rom_binary = bytearray(open(fname, 'rb').read())
        self.parse_ecu_rom()

    def show_ecu_info(self):
        self.parse_ecu_rom()
        print('fi_cut: %.1f [km/h]' % self.fi_cut_speed)
        print('fi_restart: %.1f [km/h]' % self.fi_restart_speed)

    def save_figs(self, ig_timing=True, dth_ne=True, pb_ne=True):
        if ig_timing:
            p = self.create_fig(self.ig_timing_map, title='Ignition Timing')
            p.savefig('ig_timing.png')
            print('ig_timing.png saved.')

        if dth_ne:
            p = self.create_fig(self.th_speed_density_map, title='θTH-Ne Map')
            p.savefig('th_speed_density_map.png')
            print('th_speed_density_map.png saved.')

        if pb_ne:
            p = self.create_fig(self.d_jetronic_map, title='Pb-Ne(D-jetronic) Map')
            p.savefig('d_jetronic_map.png')
            print('d_jetronic_map.png saved.')

    def show_figs(self, ig_timing=True, dth_ne=True, pb_ne=True):
        if ig_timing:
            print('in showing: "Ignition Timing"')
            p = self.create_fig(self.ig_timing_map, title='Ignition Timing')
            p.show()
        if dth_ne:
            print('in showing: "θTH-Ne Map"')
            p = self.create_fig(self.th_speed_density_map, title='θTH-Ne Map')
            p.show()
        if pb_ne:
            print('in showing: "Pb-Ne(D-jetronic) Map"')
            p = self.create_fig(self.d_jetronic_map, title='Pb-Ne(D-jetronic) Map')
            p.show()

    def change_speed_limit(self, fi_cutoff=140, fi_restart=137):
        self.has_unsaved_value = True
        backup_fi_cutoff = self.rom_binary[0x0A59:0x0A5B]
        x = speed2bin(fi_cutoff)
        self.rom_binary[0x0A59] = x[0]
        self.rom_binary[0x0A5A] = x[1]
        backup_fi_restart = self.rom_binary[0x0A59:0x0A5B]
        x = speed2bin(fi_restart)
        self.rom_binary[0x0A61] = x[0]
        self.rom_binary[0x0A62] = x[1]
        checksum_diff = 0
        checksum_diff = checksum_diff + backup_fi_cutoff[0] - self.rom_binary[0x0A59] + backup_fi_cutoff[1] - self.rom_binary[0x0A5A]
        checksum_diff = checksum_diff + backup_fi_restart[0] - self.rom_binary[0x0A61] + backup_fi_restart[1] - self.rom_binary[0x0A62]
        print("checksum diff: %02X" % (checksum_diff & 0xFF))

filename = 'beat_ecu_stock.BIN'
ecu = ECUParser(filename)
while True:
    print('--------------------')
    if ecu.has_unsaved_value:
        print('Source: *%s (unsaved)' % filename)
    else:
        print('Source: %s' % filename)
    cli = Bullet(
            prompt = "Main menu: ",
            margin = 4,
            choices = ["Show ECU information", "Change speed limit", "Save map plots", "Show map plots", "Save modified ROM data", "Exit"]
        )

    result = cli.launch()
    if result == 'Exit':
        sys.exit(0)

    print('--------------------')
    print('**** execute "%s"' % result)
    if result == "Show ECU information":
        ecu.show_ecu_info()
    elif result == "Change speed limit":
        while True:
            print('Enter speed of fuel cutoff point [km/h] => ')
            try:
                fi_cutoff = float(input())
                print('OK: fuel cutoff: %.1f [km/h]' % fi_cutoff)
                break
            except:
                print('Invalid value.')
                continue
        while True:
            print('Enter speed of limiter release [km/h] => ')
            try:
                fi_release_limit = float(input())
                print('OK: limit release: %.1f [km/h]' % fi_release_limit)
                break
            except:
                print('Invalid value.')
                continue

        ecu.change_speed_limit(fi_cutoff=fi_cutoff, fi_restart=fi_release_limit)
    elif result == "Save map plots":
        cli = MinMaxCheck(
                prompt = "press Space to choose map(s), and press Enter to execute save:",
                margin = 4,
                min_selections=0,
                max_selections=3,
                choices = ["Ignition Timing", "θTH-Ne", "Pb-Ne(D-jetronic)"]
            )
        result = cli.launch()
        if len(result) > 0:
            ecu.save_figs(ig_timing="Ignition Timing" in result, dth_ne="θTH-Ne" in result, pb_ne="Pb-Ne(D-jetronic)" in result)
        else:
            print('nothing to do.')

    elif result == 'Show map plots':
        cli = MinMaxCheck(
                prompt = "press Space to choose map(s): ",
                margin = 4,
                min_selections=0,
                max_selections=3,
                choices = ["Ignition Timing", "θTH-Ne", "Pb-Ne(D-jetronic)"]
            )
        result = cli.launch()
        if len(result) > 0:
            ecu.show_figs(ig_timing="Ignition Timing" in result, dth_ne="θTH-Ne" in result, pb_ne="Pb-Ne(D-jetronic)" in result)
        else:
            print('nothing to do.')
    elif result == 'Write modified ROM data':
        if not ecu.has_unsaved_value:
            print('nothing to do.')
            continue



# x = 0
# y = 0
# for i in range(0, 0x8000):
#     x = x ^ self.rom_binary[i]
#     y = (y + self.rom_binary[i]) & 0xff
#     if x == self.rom_binary[i]:
#         print("%02X" % x)
#         print("xor match %02X" % i)
#     if y == self.rom_binary[i]:
#         print("%02X" % y)
#         print("sum match %02X" % i)

minmaxcheck.py

'''
original: https://github.com/bchao1/bullet/blob/master/examples/check.py


MIT License

Copyright (c) 2019 Brian Chao

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
'''


from bullet import Check, keyhandler, styles
from bullet.charDef import NEWLINE_KEY

class MinMaxCheck(Check):
    def __init__(self, min_selections=0, max_selections=None, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.min_selections = min_selections
        self.max_selections = max_selections
        if max_selections is None:
            self.max_selections = len(self.choices)

    @keyhandler.register(NEWLINE_KEY)
    def accept(self):
        if self.valid():
            return super().accept()

    def valid(self):
        return self.min_selections <= sum(1 for c in self.checked if c) <= self.max_selections