Correction regarding MBC2 RAM enable register

Author: timakro

src/MBC2.md

@@ -36,7 +36,7 @@ the RAM enable flag or the ROM bank number.
 #### When bit 8 is clear
 
 When the least significant bit of the upper address byte is zero, the value that is written controls whether the RAM is enabled.
-When the value written to this address range is equal to `$0A`, RAM is enabled.
+When any value with `$A` in the lower 4 bits is written to this address range, RAM is enabled.
 If any other value is written, RAM is disabled.
 
 Examples of addresses that can control RAM: $0000–00FF, $0200–02FF, $0400–04FF, ..., $3E00–3EFF.