This version of spinsim supports most of the opcodes in the P2 v32b instruction set. The opcodes that are not supported are as follows:
xzero xinit xcont hubset setdacs setxfrq getxacc getbrk cogbrk brk setcy setci setcq setcfrq setcmod getrnd xoro32 skip skipf execf
skip, skipf and execf have been partially implemented, but do not handle jumps or interrupts correctly.
Spinsim runs in the P1 mode by default. It can be set to run in the P2 mode with the -t parameter. In the P2 mode, spinsim will load a P2 binary file into hub RAM, and start cog 0 with the code located at $000. A simulated serial port is supported by using the -b option. The default baud rate is 115200, but other rates can be used by specifying it with -b, such as -b9600. The serial port uses pins 63 and 62 when in the P2 mode.
Spinsim is built under Linux, MinGW or Cygwin by using the Makefile, and typing make. The Windows executable, spinsim.exe is included with this distribution.
The sub-directory verify contains five programs that have been used to test spinsim against the FPGA implementation. Approximately 150 instructions have been verified to match the hardware. The verify directory contains the original C source code and the output from running the test programs on the FPGA.
A test program can be run by going into the verify directory and typing
../spinsim -t -b testopsa.bin
The output can be redirected to a file and compared with the hardware file to verify that spinsim matches the hardware.
Spinsim supports the cordic instructions, but implements them with C functions instead of simulating the cordic hardware. The instructions xvector and xrotate are functionally equivalent to the P2, but will produce slightly different results. qdiv and qfract bit exact results as long as the quotient fits within 32 bits. It produces different results if the quotient overflows a 32-bit value. The I/O streamer is currently not supported.
Spinsim contains a simple debugger, which is enabled with the -d command-line option. The debugger prints the prompt "DEBUG>" to indicate that it is ready to accept a command. The "help" command will print the following:
Debug Commands help - Print command list exit - Exit spinsim step - Run one cycle stepx - Run next executed instruction run - Run continuously verbose # - Set verbosity level reboot - Reboot the Prop setbr cog addr - Set breakpoint for cog to addr state cog - Dump cog state peekc cog addr - Print out a cog memory location peekh addr - Print out a hub memory location
The "step" command will run one cycle, and the "stepx" command will run any non-executing cycles until it encounters an instruction that is executed. The previous command can be executed again by just pushing the enter key. This is useful for stepping where the "step" command is typed once, and the enter key can then be used to step again.
The "run" command will run until a breakpoint is encountered or ^] is typed. ^] is typed by holding down the control key and pressing the "]" key. While running, spinsim will print out the results of each cycle as controlled by the verbosity level, which is set by the "verbose" command. The verbosity level can also be set with the command-line parameter "-v#".
The verbosity levels are as follows:
0 - Disable printing 1 - Print only the executed instructions 2 - Print only the executed instructions, and show the execution results 3 - Print executed and instruction not executed due to condition code 4 - Also print instructions invalidated in the pipeline due to jumps 5 - Also print instructions that include hub and hardware waits 6 - Also print instructions that include icache waits 7 - Also print instructions waiting for a pin state 8 - Print all cycles, including waitcnt waits
The verbosity level is entered as a hexadecimal number. If the verbosity level is entered as a single digit it will apply to all cogs. If more than one digit is entered each digit will be used for each cog, starting with cog 0 for the right-most digit. As an example, a value of 456 will cause 6 to be used for cog 0, 5 for cog 1, and 4 for cog 2. All other cogs will use 0.