add PCR mode to isans_letter

diff --git a/openpower/isans_letter.mdwn b/openpower/isans_letter.mdwn
index a7c6b6792ea52da1beaddddbee80ef63bf4f34b9..03291680ac559f26f67428256a556067084f03a8 100644 (file)
--- a/openpower/isans_letter.mdwn
+++ b/openpower/isans_letter.mdwn
@@ -10,6 +10,7 @@ already found in the POWER instruction set, are added:
 * FPSCR's "NI" bit, setting non-IEEE754 FP mode
 * MSR's "LE" bit (and associated HILE bit), setting little-endian mode
 * MSR's "SF" bit, setting either 32-bit or 64-bit mode
+* PCR's "compatibility" bits 60-62, V2.05 V2.06 V2.07 mode
 
 All of these are set by one instruction, that, once set, radically
 changes the entire behaviour and characteristics of subsequent instructions.