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#-----------------------------------------
# NXP lpc1114fn23 Cortex-M0 32k flash, 4k ram

set CHIPNAME lpc1114
set CPUTAPID 0x0BB11477
set CPUROMSIZE 0x8000
set CPURAMSIZE 0x1000

# After reset the chip is clocked by the ~12MHz internal RC oscillator.
# When board-specific code (reset-init handler or device firmware)

ddm

Adventures in Python Core Dumping

After watching Bryan Cantrill's presentation on [Running Aground: Debugging Docker in Production][aground] I got all excited (and strangely nostalgic) about the possibility of core-dumping server-side Python apps whenever they go awry. This would theoretically allow me to fully inspect the state of the program at the point it exploded, rather than relying solely on the information of a stack trace.

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// A round-robin priority arbiter for valid/ready signaling using carry chain logic.
module arbiter#(parameter N = 2)
(
    input   wire            clk,
    input   wire    [N-1:0] s_valid,
    output  wire    [N-1:0] s_ready,
    output  wire            m_valid,
    input   wire            m_ready
);

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From this paper: http://fpgacpu.ca/fpga/hdl/Tumbush%20DVCon%2005.pdf

1. If any operand in an operation is unsigned the entire operation is unsigned.
2. Investigate fully all "signed to unsigned conversion occurs" synthesis warnings. These point to incorrect functionality.
3. All signed operands will be sign-extended to match the size of the largest signed operand.
4. Type casting using $unsigned will make the operation unsigned. The operand will be extended with 0’s if necessary.
5. Type casting using $signed makes the operand signed. The operand will be sign-extended with 1's if necessary. Pad the operand with a single 0 bit before the cast if this is not desired.
6. Expression type depends only on the operands or operation; it does not depend on the LHS of the expression.

Additional points based on feedback from Owen Shepherd:

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# Simple 16 step drum machine experiment with Node and CoffeeScript
#   by Peter Cooper - @peterc
#
#   Inspired by Giles Bowkett's screencast at
#   http://gilesbowkett.blogspot.com/2012/02/making-music-with-javascript-is-easy.html
#
#   Screencast demo of this code at http://www.youtube.com/watch?v=qWKkEaKL6DQ
#
# Required:
#   node, npm and coffee-script installed