[Mega Drive] NBA Jam - EEPROM doesn't work

[remutro]

EEPROM saving doesn't work for NBA Jam, all regions, including Rev1. After saving some statistics for yourself (by entering initials), if you reset the game and re-enter your initials it will not find anything.

Looking at the contents of the .eeprom file, the entire contents are filled with 0xf so it doesn't look like information is being written out properly.

sha256: 9ee77c144505a10940976bb48e32600c83d5910c737612868ff6088faf3eb7f4
name: NBA Jam (USA, Europe)
title: NBA Jam (USA, Europe)
label: NBA JAM
label: NBA JAM
serial: GM T-081326 00
region: NTSC-U, PAL
board
memory
type: ROM
size: 0x200000
content: Program
memory
address: 0x200000
type: EEPROM
size: 0x100
content: Save
mode: X24C02
rsda: 1
wsda: 0
wscl: 1