Silicon Programming The UP3 core library input and output for the Altera board random number generation 1 We will be covering material from chapters 4,5,10,11 on I/O I/O is the "hardest" type of module to build, since it requires transition between
electrical domain and other energy domains (e.g., mechanical, light) We will also discuss a way to generate pseudo random numbers (Appendix A) Both I/O and random number generation will probably be useful for your project. 2 UP3 functions: an IP (intellectual property) core described in chapter 5 of text VHDL versions are available 8 modules--perform I/O housekeeping functions use in project: example VHDL packageUP3pack.vhd modules must be visible in your path or included in your design in some way (directly, package, etc.)
3 module names: Debounce pushbuttons OnePulse LCD_DisplayLCD panel character display Clk_Div--gives slower clock speeds VGA_Syncvideo sync generation output Char_ROM--codes for display characters Keyboard--keyboard connector Mouse--mouse connector input 4
parallel port VGA port UP3 BOARD PS2 port Cyclone chip USB port SRAM serial port FLASH invalid input voltage LED on/off switch
user-definable pushbuttons user-definable LEDs power +3.3V supply LED user-definable DIP switches +5V supply LED
global reset LC Display http://users.ece.gatech.edu/~hamblen/UP3/ and http://users.ece.gatech.edu/~hamblen/UP3/UP3%20Reference %20Manual.pdf 5 COMPONENT LCD_Display PORT (Hex_Display_Data: IN STD_LOGIC_VECTOR (Num_Hex_Digists*4)-1 DOWNTO 0; reset, clock_48MHz: IN std_logic; LCD_RS, LCD_E: OUT STD_LOGIC; DATA_BUS: INOUT STD_LOGIC_VECTOR (7 DOWNTO 0); END COMPONENT; input 4 bits hex digit signal values to convert to ASCII hex digits and send to LED display (note: Appendix D contains ASCII to hex table) Num_Hex_Digits is a Generic parameter which can be given a value in a VHDL file or in a schematic (16 characters, 2 lines available)
Outputs LCD_RS LCD_E LCD_RW DATA_BUS (7 DOWNTO 0): PIN (important!) 108 50 73 113, 106, 104, 102, 100, 98, 96, 94 6 COMPONENT Debounce PORT (pb, clk_100Hz:IN STD_LOGIC; pb_debounced:OUT STD_LOGIC); END COMPONENT; pb is the input from a pushbutton (see I/O pins, chapter 2) since pushbuttons have a mechanical bounce, this component samples the input
over several clock cycles and filters out the bounces; it will register the pushbutton input only when several sequential samples of the input agree the clock input is used by the bounce filter (see example below) when push is registered, output goes low: it remains low until button is released 7 COMPONENT OnePulse PORT (PB_debounced, clock:IN STD_LOGIC; PB_single_pulse:OUT STD_LOGIC); END COMPONENT; after the push button signal is debounced, this component can be used to ensure that the output read from the pushbutton is high for only one clock cycle, no matter how long the pushbutton is held down this is useful for building finite state machines--an edge-triggered flip-flop can be used to build a state and each input will be active for only one clock cycle the clock input is the clock signal being used to drive the state machine 8
COMPONENT Clk_Div PORT ( clock_48MHz: IN STD_LOGIC; clock_1MHz, clock_100KHz, clock_10KHz, clock_1KHz, clock_100Hz, clock_10Hz, clock_1Hz: OUT STD_LOGIC) END COMPONENT; the input is from the (48MHz) on-board clock (pin 29 for the Cyclone chip); JP3 jumper must be set to select the 48MHz USBthis the default setting the outputs are clock signals of various frequencies which can be used in designs Note: actual frequency will be (listed frequency)*(1.007 +/- .005%) 9 Example: pushbutton Debounce
Clock (pin 29) OnePulse fsm Clock_100Hz Clk_Div Clock_1MHz 10 COMPONENT Mouse PORT ( clock_48Mhz,reset: IN STD_LOGIC; mouse_data, mouse_clk:INOUT STD_LOGIC;
left_button,right_button: OUT STD_LOGIC; mouse_cursor_row,mouse_cursor_column: OUT STD_LOGIC_VECTOR(9 DOWNTO 0); END COMPONENT; the input is from the (48MHz) on-board clock (pin 29 for the Cyclone chip); mouse_data is pin 13, mouse_clk is pin 12: BIDIRECTIONAL (also used for keyboard) cursor outputs give postion in 640 x 480 pixel screen (VGA); cursor is initialized to the middle of the screen button outputs are high when the corresponding button is pushed 11 COMPONENT Keyboard PORT ( keyboard_clk,keyboard_data, clock_48Mhz, reset, read: IN STD_LOGIC; scan_code: OUT STD_LOGIC_VECTOR(7 DOWNTO 0); scan_ready: OUT STD_LOGIC); END COMPONENT; Reads PS/2 keyboard scan code; converts serial data from keyboard to parallel
clock input is from the (48MHz) on-board clock (pin 29 for the Cyclone chip); keyboard_data is pin 13, keyboard_clk is pin 12: INPUTS (also used for mouse) read clears the scan_ready signal; reset clears flip-flops for serial-to-parallel conversion scan_code: table of values in Table 11.3; --make code: key is hit; break code: key is released ex: A make = 1C, break = F01C: shift make = 12, break = F012 (if key is held down, several makes will be sent before a break) scan_ready goes high when new scan code is sent and can be used to make sure each scan 12 code is read only once COMPONENT VGA_Sync PORT (clock_48MHz, red, green, blue: IN STD_LOGIC; red_out, green_out, blue_out, horiz_sync_out, vert_sync_out: OUT STD_LOGIC; pixel_row, pixel_column: OUT STD_LOGIC_VECTOR(9 DOWNTO 0)); END COMPONENT; clock_48MHz signal must come from pin 29 (Cyclone chip)
user logic generates the input color (red, green, blue) Cyclone chip: horiz_sync --> pin 226, vert_sync --> pin 227 red_out --> pin 228, green_out --> pin 122, blue_out --> pin 170 pixel_row and pixel_column give the pixel address how many colors are available? how many pixels? (dithering: one color on odd cycles, different on even twice as many colors example: pattern sent (even/odd cycles) pattern observed 13 COMPONENT Char_ROM PORT (clock: IN STD-logic; character_address: IN STD_LOGIC_VECTOR (5 DOWNTO 0); font_row, font_col: IN STD_LOGIC_VECTOR (2 DOWNTO 0); row_mux_output: OUT STD_LOGIC); END COMPONENT;
generates text for a video display--each character requires an 8 x 8 pixel pattern (see codes, table 9.1--a memory initialization file, tcgrom.mif, is provided; the font data can be stored in one M4K memory block) character_address addresses the character to be displayed font_row and font_col step through the 64 pixels (8x8) needed to display one character Clock loads the address register and should be tied to the video pixel_clock row_mux_output is the pixel value to be output for this character at this position and can be used to generate the correct RGB pixel color 14 How does output occur (examples: chapter 10): monitor contains CRT (cathode ray tube) screen consists of pixels, 640 in a row and 480 in a column (VGA format) refresh rate: how quickly these pixels are scanned 640 standard rate is 60 times / second (60 Hz)
(human eye can detect flicker below 30Hz) 480 if there are 640 X 480 pixels, with a 60Hz refresh rate, how much time is available to scan one pixel? What clock speed is therefore required? What is the onboard clock speed? (note: UP3 has PLL which can be used to obtain faster refresh rates) Sync signals tell when to start a new row or column 15 random number generation (Appendix A): actually generates pseudorandom numbers Q: what is the difference? Method: example: n = 32--will give 32-bit pseudorandom sequence of bits from table, read XOR from bits 32,22,2,1 (bits are 32--1, not 31--0) build a 32-bit shift register that shifts left one bit per cycle
next bit to be input into lsb should be the XOR of bits 32,22,2,1 this will generate a sequence in pseudorandom order initial value in the register is the seed; 0 should not be used (why?) 16 Example: n = 3--table gives bits 3,2 step pattern (bit 3) xor (bit 2) 0 1 2 3 4 5 6 7
111 110 100 001 010 101 011 111 0 0 1 0 1 1 1 0---from here, the sequence will repeat
we have a sequence of the numbers 1-7: 7,6,4,1,2,5,3 this is the longest nonrepeating sequence we can have order will always be the same, seed only determines where we start 17 How good are the random numbers generated? Reference: Shruthi Narayanan, M.S. 2005, ATI Technologies Hardware implementation of genetic algorithm modules for intelligent systems: Random numbers generated by one shift register Random numbers generated by multiple shift registers 18
