The GH VHDL Library
Revision 3.48 ii 7 March 2009
Revision History
Revision Date Author Description
1.0 3 Sept 2005 G Huber Initial Revision
1.1 10 Sept 2005 G Huber Add parts, fix some typo’s
2.0 17 Sept 2005 H LeFevre
1. Add LFSR’s
2. Add gh_ prefix to the name of some parts.
(See chapter 4 for explanation on this change)
3 Mod parts to use gh_ parts (where required)
2.1 18 Sept 2005 G Huber Add decoder/mux, clock divider, and NCO
2.2 24 Sept 2005 S A Dodd Add pulse generator
2.3 1 Oct 2005 G Huber Add sweep generator
2.4 4 Oct 2005 H LeFevre
Add Random Number Generator/CASR
3.0 8 Oct 2005 G Huber Reorganize library,
add a couple of shift registers
3.1 15 Oct 2005 S A Dodd Add parity generator, FIFO’s, integer counters
3.2 23 Oct 2005 G Huber Add programmable LFSR’s
3.3 29 Oct 2005 G Huber Add Configuration Registers
3.4 13 Nov 2005 S A Dodd,
G Huber
Add some memory parts
3.5 14 Jan 2006 G Huber Add delay lines
3.6 21 Jan 2006 S A Dodd
G Huber
Add Control Registers
Add a fixed delay line for a bus
3.7 28 Jan 2006 H LeFevre
Add a baud rate generator
3.8 4 Feb 2006 S A Dodd
H LeFevre
Add FIFO with sync clear
Add an In Place Multiplier
3.9 11 Feb 2006 H LeFevre
G Huber
Add two more In Place Multipliers (one has both
inputs unsigned and the other both inputs are
signed)
Add another shift register (shifts left)
3.10 18 Feb 2006 G Huber Add another shift register (also shifts left)
Finished adding the gh_ prefix to all parts
3.11 25 Mar 2006 H LeFevre
S A Dodd
Add one more In Place Multiplier
Mod gh_sincos to use Cordic + 45
3.12 13 May 2006 S A Dodd Add FIR Filter
3.13 26 May 1006 G Huber Add debounce, stretch low
3.14 16 Sept 2006 G Huber Add a counter, 18 bit multipliers
3.15 23 Sept 2006 SA Dodd Add complex math parts
3.16 23 Dec 2006 H LeFevre
Replace async FIFO (to use gray code)
3.17 27 Dec 2006 G Huber
HL/SD
Add Gray code converters
Update FIFO’s
3.18 13 Jan 2007 H LeFevre
add async FIFO’s with ¼. ½, and ¾ full flags
3.19 27 Jan 2007 SA Dodd add digital attenuator
3.20 3 Feb 2007 H LeFevre
add parallel FIR Filter
3.21 10 Feb 2007 H LeFevre
add FIR Filters of odd order, negative symmetry
The GH VHDL Library
Revision 3.48 iii 7 March 2009
3.22 9 June 2007 G Huber
SA Dodd
add programmable delay bus, FASM dual port Ram
with reset, 3 multipliers with generics
3.23 30 June 2007 H LeFevre
G Huber
add 2 in-place multipliers, with all data bits out
add MAC with full generics and an unsigned array
divider
3.24 15 July 2007 S A Dodd add a FIR filter and Pulse time/width module
3.25 12 Aug 2007 S A Dodd mod/add filter
3.26 16 Aug 2007 S A Dodd add (two clock multiply) complex multipliers
3.27 14 Oct 2007 H LeFevre
add some filters w/o multipliers
3.28 21 Oct 2007 S A Dodd
G Huber
Add rev A of rectangular to polar (CORDIC
application) – increases pipelining
add 4 byte memory
3.29 22 Nov 2007 H LeFevre
add VMEbus Slave Interface Module parts
3.30 25 Nov 2007 H LeFevre
add FIR filter, rev A for NCO
3.31 8 Dec 2007 G Huber add VME read Modules
3.32 30 Dec 2007 H LeFevre
add 3 multiplier complex multipliers
3.33
3.33a
3 May 2008
4 May 2008
H LeFevre
Add random number scalar (serial multiplier)
Add random number scalar (parallel multiplier)
3.34 24 May 2008 H LeFevre
Add two asynchronous fifo’s (with UART style
flags)
3.35 27 May 2008 G Huber Add programmable delay line using generics
3.36 1 June 2008 S A Dodd
3 complex multipliers, with an extra register
delay for higher operating frequency
Data Mux(2:1) /DeMux (1:2) set
3.37 4 July 2008 G Huber Add some NCO type accumulators
3.38 1 Sept 2008 H LeFevre
Add versions of a couple frequency syntheses parts
3.39 20 Sept 2008 H LeFevre
Add programmable Stretch parts, add init to some
of the memory parts
3.40 27 Sept 2008 H LeFevre
Add 4 byte GPIO
3.41 04 Oct 2008 H LeFevre
Add Burst Generator
3.42 11 Oct 2008 H LeFevre
Add CORDIC’s with 28 bit atan functions
3.43 26 Oct 2008 H LeFevre
Add Sin Cos ROM’s
3.44 1 Nov 2008 H LeFevre
Add Sin Cos ROM’s with quarter size tables
3.45 8 Nov 2008 H LeFevre
Add config registers (3072, 4096 bits), fix notes
3.46 25 Jan 2009 H LeFevre
Add watch dog timers
3.47 28 Feb 2009 H LeFevre
Add Pulse Width Modulator
3.48 7 Mar 2009 H LeFevre
Add NCO’s that use Lookup tables for nsin/cos
The GH VHDL Library
Revision 3.48 iv 7 March 2009
Table of Contents
1 Introduction................................................................................................................. 1
1.1 Purpose................................................................................................................ 1
1.2 What the Library is Not ...................................................................................... 1
1.3 GH VHDL License ............................................................................................. 1
2 Basic Registers and Gates........................................................................................... 3
2.1 D Flip Flop.......................................................................................................... 3
2.2 JK Flip Flop ........................................................................................................ 3
2.3 Basic Register and Latch .................................................................................... 4
2.4 XOR Bus............................................................................................................. 4
2.5 Comparators........................................................................................................ 5
2.6 Decoders ............................................................................................................. 6
2.7 Multiplexers........................................................................................................ 6
2.8 Shift Registers..................................................................................................... 7
2.9 Four Byte Configuration Registers ..................................................................... 8
3 Counters...................................................................................................................... 9
3.1 Binary Counters .................................................................................................. 9
3.2 Modulo Counter................................................................................................ 10
3.3 Integer Counters................................................................................................ 10
4 Custom MSI Parts..................................................................................................... 11
4.1 Pulse Stretcher .................................................................................................. 11
4.2 Edge Detector.................................................................................................... 12
4.3 Clock Divider.................................................................................................... 12
4.4 Pulse Generator................................................................................................. 13
4.5 Parity Generator................................................................................................ 13
4.6 Delay Lines....................................................................................................... 14
4.7 Baud Rate Generator......................................................................................... 15
4.8 Control Registers .............................................................................................. 16
4.9 A Switch de-bouncer......................................................................................... 17
4.10 An Edge Detector for changing Clock Domains .............................................. 17
4.11 Gray code converters ........................................................................................ 18
4.12 Pulse Width/Time Measurement....................................................................... 18
4.13 Lower Rate Clock Mirror.................................................................................. 19
4.14 Data DeMux 1 to 2............................................................................................ 19
4.15 Data Mux 2 to 1 ................................................................................................ 20
4.16 Four Byte GPIO................................................................................................ 20
4.17 Burst Generator................................................................................................. 21
4.18 Watch Dog Timers............................................................................................ 22
4.19 Pulse Width Modulator..................................................................................... 22
5 Math Functions ......................................................................................................... 24
5.1 Accumulator...................................................................................................... 24
5.2 Multipliers......................................................................................................... 24
5.3 Multipliers using Generics................................................................................ 25
5.4 Multiplier Accumulator .................................................................................... 25
5.5 Random Number Generation ............................................................................ 26
The GH VHDL Library
Revision 3.48 v 7 March 2009
5.5.1 The Linear Feedback Shift Register (LFSR) ............................................ 26
5.5.2 CASR and Random Number Generator.................................................... 27
5.5.3 Programmable LFSR’s.............................................................................. 28
5.5.4 Random Number Scalars .......................................................................... 29
5.6 In Place Multipliers........................................................................................... 30
5.7 Unsigned Array Divider.................................................................................... 31
5.8 Complex Math .................................................................................................. 32
5.9 Digital Attenuator ............................................................................................. 34
6 Memory..................................................................................................................... 35
6.1 Synchronous RAM............................................................................................ 35
6.2 FIFO’s............................................................................................................... 36
6.2.1 Synchronous FIFO.................................................................................... 36
6.2.2 Asynchronous FIFO.................................................................................. 37
6.2.3 Asynchronous FIFO’s with UART Style Flags........................................ 38
6.3 Four Byte Dual Port RAM................................................................................ 39
7 Frequency Synthesis ................................................................................................. 40
7.1 The DDS (also known as the NCO, or DCO)................................................... 40
7.1.1 NCO Style Accumulators ......................................................................... 41
7.2 Sweep Generator............................................................................................... 42
7.2.1 Simulation of the Sweep Generator.......................................................... 45
7.3 CORDIC Rotation Algorithm........................................................................... 46
7.3.1 Theory of the CORDIC............................................................................. 47
7.3.2 Applications for the CORDIC .................................................................. 49
7.4 Sin Cos ROM Lookup Tables........................................................................... 50
8 Filters ........................................................................................................................ 51
8.1 CIC Filter .......................................................................................................... 51
8.2 Time–Varying Fractional Delay Filters............................................................ 54
8.2.1 The Lagrange Interpolator ........................................................................ 54
8.2.2 Time–Varying Control.............................................................................. 55
8.2.3 TVFD Application Notes.......................................................................... 55
8.3 A single MAC FIR Filter.................................................................................. 56
8.4 Symmetrical, parallel FIR Filters...................................................................... 57
8.4.1 FIR Filter Architecture.............................................................................. 58
8.5 FIR Filters Without Multipliers ........................................................................ 59
9 VMEbus [VXIbus] Interface Modules...................................................................... 60
9.1 VME Slave Modules......................................................................................... 61
9.2 VME Chip Select Modules ............................................................................... 63
9.3 VME Read Modules ......................................................................................... 63
10 Library Notes ........................................................................................................ 64
