L'Empereur/ROM map: Difference between revisions

Revision as of 05:02, 4 January 2019

The following article is a ROM map for L'Empereur.

Note that most functions in this game are essentially written in a higher-level computer language than 6502. By using a jump table, more complex operations are able to be identified by single hex codes. These functions are prefaced by "20 09 E5 ## ##" (JSR $E509) and terminated by the operation "CF". (## ## indicates how many memory spaces need to be dedicated to the new function, written as an inverse. A function that requires no new memory space will say "00 00", while one that requires 16 spaces will say "F0 FF".

Sometimes one of these functions will jump to a subroutine which is written "normally" (without upper-level operations). These routines are prefaced by "20 E3 E2 ## ## ##" (JSR $E2E3).

A list of these operations is located here. This same system seems to be used by the other MMC5 Koei games.

Page E0 ($A000-$BFFF)

ROM location: 0x00010-0x0200F

E0:A03A

Prints graphic (5) to tile coordinates (1),(3)

E0:A2CC

Checks if City 1 (1/2) can sail to City 2 (3/4). (5) = whether sea control matters

E0:A327

Checks if it's safe to sail from City (1/2). Returns 0 if city is landlocked or sea is controlled by a hostile nation; otherwise, returns 1.

E0:A39C

Checks if officer (1/2) is player-controlled.

E0:A3E0

Checks if commander of city (1/2) is player-controlled.

E0:A425

Checks if city (1/2) is adjacent to city (3/4) [by either land or sea]

E0:A805

Check if nation (3/4) exists. (Parameter 1/2 serves no function?)

E0:A8A0

Verifies checksum when loading game(?)

E0:A99D

Erase sprites #(1) to #(1)+(3)

E0:BC7E

Determines which nation has control of sea (1/2).

00 = Baltic, 01 = North, 02 = Atlantic, 03 = Mediterranean

Page E1 ($8000-$9FFF)

ROM location: 0x02010-0x0400F

E1:86B6

Print graphic (1) to coordinate 16,14.

E1:8A1A

Prints the text "More will have no effect" & waits 3 time units for input before advancing.

E1:8A2C

Prints the text "No [x]", where [x] is entry #(1) in Page F8, Table 3

E1:8BA5

Identifies map location of city (01/02) from table $9F9F

E1:8BB8

Center map on city (1/2) and change banner to nation (3/4)

E1:8C4A

Retrieve text string (1) from Page F7.

E1:8C5B

Retrieve text string (1) from Page F8.

E1:8C6C

Retrieve text string (1) from Page F9 (Table $B076).

E1:8C8E

Retrieve text string (1) from Table 2 of Page F7

E1:8CA8

Retrieve text string (1) from Table 3 of Page F7

E1:8D4B

Print text string (1/2) as an officer quote.

E1:8DF1

Returns the difference in French aggression values between nations (1/2) and (3/4).

E1:9D13

Finds the officer in a city with the best given stat.

E1:9D73

Checks if France has won the game (captured all cities).

E1:9F9F

Table of cities by their map locations.

01 = Northwest, 02 = Northeast, 03 = Southwest, 04 = Southeast

01 DUBLIN       01
02 EDINBURGH    01
03 LIVERPOOL    01
04 BRISTOL      01
05 LONDON       01
06 CHRISTIANIA  01
07 STOCKHOLM    02
08 COPENHAGEN   01
09 AMSTERDAM    01
10 LUBECK       01
11 BERLIN       01
12 WARSAW       02
13 KONIGSBERG   02
14 STPETERSBURG 02
15 MINSK        02
16 SMOLENSK     02
17 MOSCOW       02
18 KIEV         02
19 KLAUSENBURG  04
20 BUCHAREST    04
21 BUDAPEST     04
22 VIENNA       04
23 PRAGUE       02
24 MUNICH       03
25 FRANKFURT    01
26 LILLE        01
27 ST.MALO      03
28 PARIS        03
29 BORDEAUX     03
30 LYON         03
31 MARSEILLES   03
32 MILAN        03
33 FLORENCE     04
34 VENICE       04
35 SARAJEVO     04
36 BELGRADE     04
37 ROME         04
38 NAPLES       04
39 ISTANBUL     04
40 ATHENS       04
41 CORUNNA      03
42 LISBON       03
43 GIBRALTAR    03 
44 MADRID       03
45 SARAGOSSA    03
46 BARCELONA    03

Page E2 ($A000-$BFFF)

ROM location: 0x04010-0x0600F

Page E3 ($A000-$BFFF)

ROM location: 0x06010-0x0800F

Page E4 ($A000-$BFFF)

ROM location: 0x08010-0x0A00F

Page E5 ($A000-$BFFF)

ROM location: 0x0A010-0x0C00F

Page E6 ($A000-$BFFF)

ROM location: 0x0C010-0x0E00F

Page E7 ($A000-$BFFF)

ROM location: 0x0E010-0x1000F

Page E8 ($A000-$BFFF)

ROM location: 0x10010-0x1200F

Contains functions pertaining to CPU actions during the city phase.

E8:A8DF

Main function for all CPU city actions.

A8E4 AA D1 7C    / Push $7CD1/$7CD2 to stack / (+2) Active city
A8E7 E9 DB BA 02 / Run function $BADB        / (-2)

...

E8:BADB

Page FA ($A000-$BFFF)

FA:A004

Table of Nations

$A004 + #$0A x (Nation code) = Beginning of nation data starting with name and ending with hidden stat.

FA:A09A

Table of Cities

$A09A + #$20 x (City code) = Beginning of city data starting with name and ending with hidden stat.

FA:A650

Table of Officers

$A650 + #$11 x (Officer code) = Beginning of officer data starting with name and ending with hidden stat.

See Notes for more detail on hidden stats.

Page FE ($C000-$DFFF)

ROM location: 0x3C010-0x3E00F

FE:C003

Main game loop. Executes all game functions then waits until interrupt

C008 61          / Push #$01 to stack           / (+2)
C009 E9 6F CF 02 / Run function $CF6F           / (-2)
C00D 8D 1F       / Push #$1F to stack           / (+2)
C00F 60          / Push #$00 to stack           / (+2)
C010 E9 C9 CF 04 / Run function $CFC9           / (-4)
C014 8D 14       / Push #$14 to stack           / (+2)
C016 67          / Push #$07 to stack           / (+2)
C017 E9 BC C3 04 / Run function $C3BC           / (-4)
C01B AA 00 60    / Push $6000/$6001 to stack    / (+2)
C01E 8E 16 DF    / Push #$DF16 to stack         / (+2)
C021 E9 27 C6 04 / Run function $C627           / (-4)
C025 61          / Push #$01 to stack           / (+2)
C026 64          / Push #$04 to stack           / (+2)
C027 E9 1E EF 04 / Run function $EF1E           / (-4)
C02B B3          / Push M8 to stack             / (+2)
C02C 8E 22 DF    / Push #$DF22 to stack         / (+2)
C02F E9 27 C6 04 / Run function $C627           / (-4)
C033 62          / Push #$02 to stack           / (+2)
C034 64          / Push #$04 to stack           / (+2)
C035 E9 1E EF 04 / Run function $EF1E           / (-4)
C039 B3          / Push M8 to stack             / (+2)
C03A 8E 2A DF    / Push #$DF2A to stack         / (+2)
C03D E9 27 C6 04 / Run function $C627           / (-4)
C041 D6 41 C0    / Jump to $C041                / Stall until interrupt
C042 CF          / Exit

FE:C232

Officer gains 1 EXP.

Parameter 1/2 = Officer address

C237 0C          / Store parameter 1/2 to M8    / Officer address
C238 76          / Add #$06 to M8               / Officer exp address
C239 2B          / Store M8 to storage 1/2      
C23A 0B          / Store storage 1/2 to M8      
C23B B3          / Push M8 to stack             / (+2)
C23C D3          / Replace M8 with 1-byte value / Officer exp (old)
C23D D0          / Increment M8                 / +1 exp
C23E D4          / Pull 2 meta, store $0008     / (-2) Update exp
C23F 0B          / Store meta 01/02 to M8 
C240 D3          / Replace M8 with 1-byte val   / Officer exp (new)
C241 8B 64       / Store #$64 to MC             
C243 C9          / Check if M8 >= MC            / Check if 100+
C244 D8 4F C2    / Jump to $C24F if not         / Exit
C247 3B          / Push storage 1/2 to stack    / (+2)
C248 40          / Store #$00 to M8
C249 D4          / Pull 2 meta, store $0008     / (-2) Roll EXP over to 00
C24A 3C          / Push params 1/2 to stack     / (+2)
C24B E9 D6 C1 02 / Run function $C1D6           / (-2) Officer Levels Up
C24F CF          / Exit

Page FF ($E000-$FFFF)

FF:E2E3

Prep for assembly functions.

FF:E509

Prep for higher-level functions.