diff options
Diffstat (limited to 'gr-digital/lib/glfsr.cc')
| -rw-r--r-- | gr-digital/lib/glfsr.cc | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/gr-digital/lib/glfsr.cc b/gr-digital/lib/glfsr.cc index fa6c765570..5593bf8615 100644 --- a/gr-digital/lib/glfsr.cc +++ b/gr-digital/lib/glfsr.cc @@ -1,6 +1,6 @@ /* -*- c++ -*- */ /* - * Copyright 2007,2012 Free Software Foundation, Inc. + * Copyright 2007,2012,2016 Free Software Foundation, Inc. * * This file is part of GNU Radio * @@ -26,7 +26,7 @@ namespace gr { namespace digital { - static int s_polynomial_masks[] = { + static uint32_t s_polynomial_masks[] = { 0x00000000, 0x00000001, // x^1 + 1 0x00000003, // x^2 + x^1 + 1 @@ -59,19 +59,28 @@ namespace gr { 0x10000002, // x^29 + x^2 + 1 0x20000029, // x^30 + x^4 + x^1 + 1 0x40000004, // x^31 + x^3 + 1 - (int) 0x80000057 // x^32 + x^7 + x^5 + x^3 + x^2 + x^1 + 1 + 0x80000057 // x^32 + x^7 + x^5 + x^3 + x^2 + x^1 + 1 }; glfsr::~glfsr() { } - int glfsr::glfsr_mask(int degree) + uint32_t glfsr::glfsr_mask(unsigned int degree) { if(degree < 1 || degree > 32) - throw std::runtime_error("glfsr::glfsr_mask(): degree must be between 1 and 32 inclusive"); + throw std::runtime_error("glfsr::glfsr_mask(): degree must be between 1 and 32 inclusive"); return s_polynomial_masks[degree]; } + uint8_t glfsr::next_bit() + { + unsigned char bit = d_shift_register & 0x1; + d_shift_register >>= 1; + if(bit) + d_shift_register ^= d_mask; + return bit; + } + } /* namespace digital */ } /* namespace gr */ |