diff --git a/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper028.cs b/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper028.cs
index 6455713fc9..d32b11070d 100644
--- a/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper028.cs
+++ b/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper028.cs
@@ -61,18 +61,18 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 					break;
 				case 0x10:
 				case 0x14:
-					prglo = outb & ~2 | prg & 2;
-					prghi = outb & ~2 | prg & 2 | 1;
+					prglo = outb & ~2 | prg << 1 & 2;
+					prghi = outb & ~2 | prg << 1 & 2 | 1;
 					break;
 				case 0x20:
 				case 0x24:
-					prglo = outb & ~6 | prg & 6;
-					prghi = outb & ~6 | prg & 6 | 1;
+					prglo = outb & ~6 | prg << 1 & 6;
+					prghi = outb & ~6 | prg << 1 & 6 | 1;
 					break;
 				case 0x30:
 				case 0x34:
-					prglo = outb & ~14 | prg & 14;
-					prghi = outb & ~14 | prg & 14 | 1;
+					prglo = outb & ~14 | prg << 1 & 14;
+					prghi = outb & ~14 | prg << 1 & 14 | 1;
 					break;
 				// bottom fixed modes
 				case 0x08: