diff --git a/README.md b/README.md
index 3a110f8..394dedc 100644
--- a/README.md
+++ b/README.md
@@ -6,6 +6,9 @@ Current support:
 * Digilent arty Artix xc7a35ti (memory and spi flash)
 * Lattice MachXO3LF Starter Kit LCMX03LF-6900C (flash)
 
+Supported cables:
+* JTAG-HS3: jtag programmer cable from digilent
+
 ## compile and install
 
 This application uses **libftdi1**, so this library must be installed (and,
diff --git a/cable.hpp b/cable.hpp
index bd4e549..39261d6 100644
--- a/cable.hpp
+++ b/cable.hpp
@@ -7,6 +7,7 @@
 
 static std::map <std::string, FTDIpp_MPSSE::mpsse_bit_config > cable_list = {
 	{"digilent", {0x0403, 0x6010, 0xe8, 0xeb, 0x00, 0x60}},
+	{"digilent_hs3", {0x0403, 0x6014, 0x88, 0x8B, 0x20, 0x30}},
 	{"ft2232",   {0x0403, 0x6010, 0x08, 0x0B, 0x08, 0x0B}},
 	{"altera",   {0xcafe, 0xbebe, 0x08, 0x0B, 0x08, 0x0B}}
 };
diff --git a/ftdijtag.cpp b/ftdijtag.cpp
index d69861a..5298c7a 100644
--- a/ftdijtag.cpp
+++ b/ftdijtag.cpp
@@ -204,8 +204,8 @@ int FtdiJtag::read_write(unsigned char *tdi, unsigned char *tdo, int len, char l
 	unsigned char tx_buf[3] = {(unsigned char)(MPSSE_LSB | MPSSE_WRITE_NEG |
 							   ((tdi) ? MPSSE_DO_WRITE : 0) |
 							   ((tdo) ? (MPSSE_DO_READ | MPSSE_READ_NEG) : 0)),
-							   ((xfer - 1) & 0xff),		// low
-							   (((xfer - 1) >> 8) & 0xff)};	// high
+							   static_cast<unsigned char>((xfer - 1) & 0xff),		// low
+							   static_cast<unsigned char>((((xfer - 1) >> 8) & 0xff))};	// high
 
 	flushTMS(true);