diff --git a/adafruit_epd/ssd1680.py b/adafruit_epd/ssd1680.py
index 95a94d6..30c032e 100644
--- a/adafruit_epd/ssd1680.py
+++ b/adafruit_epd/ssd1680.py
@@ -73,13 +73,14 @@ _SSD1680_WRITE_USERID = const(0x38)
 _SSD1680_OTP_PROGMODE = const(0x39)
 _SSD1680_WRITE_BORDER = const(0x3C)
 _SSD1680_END_OPTION = const(0x3F)
+_SSD1680_READ_RAM_OPT = const(0x41)
 _SSD1680_SET_RAMXPOS = const(0x44)
 _SSD1680_SET_RAMYPOS = const(0x45)
 _SSD1680_AUTOWRITE_RED = const(0x46)
 _SSD1680_AUTOWRITE_BW = const(0x47)
 _SSD1680_SET_RAMXCOUNT = const(0x4E)
 _SSD1680_SET_RAMYCOUNT = const(0x4F)
-_SSD1680_NOP = const(0xFF)
+_SSD1680_NOP = const(0x7F)
 
 
 class Adafruit_SSD1680(Adafruit_EPD):
diff --git a/adafruit_epd/ssd1680b.py b/adafruit_epd/ssd1680b.py
index 62ded36..f7b0132 100644
--- a/adafruit_epd/ssd1680b.py
+++ b/adafruit_epd/ssd1680b.py
@@ -69,13 +69,14 @@ _SSD1680B_WRITE_USERID = const(0x38)
 _SSD1680B_OTP_PROGMODE = const(0x39)
 _SSD1680B_WRITE_BORDER = const(0x3C)
 _SSD1680B_END_OPTION = const(0x3F)
+_SSD1680B_READ_RAM_OPT = const(0x41)
 _SSD1680B_SET_RAMXPOS = const(0x44)
 _SSD1680B_SET_RAMYPOS = const(0x45)
 _SSD1680B_AUTOWRITE_RED = const(0x46)
 _SSD1680B_AUTOWRITE_BW = const(0x47)
 _SSD1680B_SET_RAMXCOUNT = const(0x4E)
 _SSD1680B_SET_RAMYCOUNT = const(0x4F)
-_SSD1680B_NOP = const(0xFF)
+_SSD1680B_NOP = const(0x7F)
 
 
 class Adafruit_SSD1680B(Adafruit_EPD):