diff --git a/Reflashing-SNES-SFC-Repros.md b/Reflashing-SNES-SFC-Repros.md
index 9406ef6..9f23a4a 100644
--- a/Reflashing-SNES-SFC-Repros.md
+++ b/Reflashing-SNES-SFC-Repros.md
@@ -26,6 +26,8 @@ For the manual options to work the flashrom needs to be on the list of supported
 - ExLoRom (P1) will write the first 4MB starting from file 0x0 to flashrom 0x400000. And then a second block up to 4MB from file 0x400000 to flashrom 0x0.    
 - ExHiRom (P1) will write the first 4MB starting from file 0x0 to flashrom 0x400000. And then a second block up to 4MB from file 0x400000 to flashrom 0x0.
 
+All the "(P1)" options are doing is flipping around A22 so the first and second half of an 8MB flashrom are getting written in reversed order.   
+
 Note: If there are two flash chips on the repro the "(P0)" option addresses the flashrom connected to MAD1 pin 16 and "(P1)" addresses the flashrom connected to MAD1 pin 1. 
 
 To program the flashrom you need to erase it, then do the blank-check and finally select write to flash it with your ROM.