diff --git a/Documentation/serprog-protocol.txt b/Documentation/serprog-protocol.txt
index 47e1071..f4e68a5 100644
--- a/Documentation/serprog-protocol.txt
+++ b/Documentation/serprog-protocol.txt
@@ -36,6 +36,8 @@
 0x14	Set SPI clock frequency in Hz	32-bit requested frequency	ACK + 32-bit set frequency / NAK
 0x15	Toggle flash chip pin drivers	8-bit (0 disable, else enable)	ACK / NAK
 0x16	Set SPI Chip Select		8-bit				ACK / NAK
+0x17	Set SPI Mode			8-bit				ACK / NAK
+0x18	Set CS Mode			8-bit				ACK / NAK
 0x??	unimplemented command - invalid.
 
 
@@ -93,6 +95,21 @@
 	0x16 (S_SPI_CS):
 		Set which SPI Chip Select pin to use. This operation is immediate,
 		meaning it doesn't use the operation buffer.
+	0x17 (S_SPI_MODE):
+		Set which SPI Mode to use for 0x13 O_SPIOP commands.
+		This operation is immediate, meaning it doesn't use the operation buffer.
+		The current defined modes are:
+			0x00: SPI Half Duplex (default)
+			0x01: SPI Full Duplex
+	0x18 (S_CS_MODE):
+		Set which CS Mode to use. The CS Mode determines the CS behaviour.
+		This allows manual control over the CS.
+		This operation is immediate, meaning it doesn't use the operation buffer.
+		The current defined modes are:
+			0x00: CS Auto Mode. The CS gets selected before 0x13 O_SPIOP commands and
+			      deselected afterwards. (default)
+			0x01: CS Selected. The CS will be selected until another mode is set.
+			0x02: CS Deselected. The CS will be deselected until another mode is set.
 	About mandatory commands:
 		The only truly mandatory commands for any device are 0x00, 0x01, 0x02 and 0x10,
 		but one can't really do anything with these commands.