cleaned up the repo a bit

README.md

@@ -21,13 +21,12 @@ The maintenance manual has flow charts, schematics and explanations:
 The code is more or less a transcription of the schematics into C.
 This means you will not understand it unless you're familiar with the maintenance manual.
 Pulses are represented as functions, when a pulse triggers another pulse
-it does so by the `nextpulse` function which adds a pulse to the list of next pulses.
-In the main cpu loop the list of current pulses is iterated and each pulse is called,
-then (after checking some external signals) the current and next pulse lists are swapped
-and the process begins anew.
-The timing was not accurately modeled and there is room for improvement.
-Due to the inexact timing the hardware connections (through the memory and IO bus)
-were not implemented too accurately. This may change in the future.
+it does so by the `pulse` function which queues a pulse in a list
+of pulses that are to happen, sorted chronologically.
+Between pulses that happen at different times
+various things are done like checking external pulses and advancing the
+simulation state.
+The timing is not yet 100% accurate but it's pretty close.
 
 ### Building
 
@@ -36,8 +35,8 @@ Otherwise you need SDL and pthread.
 
 ### Running
 
-The cpu (apr), console tty and paper tape/punch are implemented.
-There are no other external devices yet.
+The cpu (apr), console tty, paper tape and punch,
+the data control and DECtape are implemented.
 The only things missing from the cpu is the repeat key mechanism.
 
 ## Verilog Simulation
@@ -59,17 +58,72 @@ The TTY is connected to UART over GPIO pins 4 (RX) and 5 (TX)
 
 ## File tree
 
-* `emu` source for the emulator
-* `verilog` source for the verilog simulation
-* `art` everything graphical
-* `code` some test code for the PDP-6
-* `panel6` virtual panel for the FPGA
-* `tools` tools like an assembler and linker
-* `misc` some misc. and old stuff
+* emu	the C emulator
+* emu/main_panel.c	main file for emulator with panel simulation
+* emu/main_serial.c	main file for emulator with panel over serial line
+* emu/emu.c	top level emulator code
+* emu/cmd.c	command line interface
+* emu/apr.c	Arithmetic Processor 166 emulation
+* emu/mem.c	core and fast memory emulation
+* emu/tty.c	Teleprinter 626 emulator
+* emu/pt.c	Paper tape reader 760 and punch 761 emulation
+* emu/dc.c	Data Control 136 emulation
+* emu/dt.c	DECtape 551 and 555 emulation
+* emu/netmem.c	network protocol for shared memory
+* emu/util.c	various utility functions
+* emu/util.h
+* emu/test_*.c	test code, not too important anymore
+* emu/pdp6.h	main header
+* emu/args.h	argument parsing
+* emu/elements.inc	panel definition
+* emu/cmds.txt	command line interface documentation
+* emu/init.ini	emulator init file
+* emu/mem_*	core memory backing store
+
+* tools
+* tools/dtr2dta.c	convert between raw (dtr) and simh (dta) DECtape format
+* tools/mkpty.c	make a pty and connect to the controlling tty
+* tools/mkpty33.c	as above but try to pretend an ASR33
+* tools/as6.c	an assembler, roughly modeled on MACRO
+* tools/ld6.c	a loader or relocatable files
+* tools/pdp6bin.h
+* tools/pdp6common.c	useful functions for PDP-6 code
+* tools/pdp6common.h
+* tools/rel.c	I have no recollection of this code
+* tools/reltest.c	old test code to create a REL file
+* tools/test.s	old test code for the assembler/linker
+* tools/test2.s
+* tools/ptdump.c	print a paper tape file in octal
+* tools/dtdump.c	print dtr DECtape
+
+* verilog
+* verilog/apr.v	Arithmetic Processor 166 simulation
+* verilog/core161c.v	Core memory 161C simulation
+* verilog/fast162.v	Fast memory 162 simulation
+* verilog/modules.v	utility modules
+* verilog/pdp6.v		top level module
+* verilog/quartus		various files for my terasic board
+* verilog/test_dec.v	inst decoding test
+* verilog/test.v		misc tests
+* verilog/test1.inc
+* verilog/test2.inc
+* verilog/test_fp.inc
+
+* code	random code for the PDP-6, mostly testing
+* code/bootstrap.txt	a list of boot loaders
+* code/dtboot.s		loads the first block from a DECtape
+* code/main.s		random entry
+* code/tty.s		tty character IO
+
+* panel	stand alone panel with lots of duplicate code
+
+* art	image files for the panel
+
+* misc	nothing important
 
 ## To do
 
 - repeat and maint. switches
-- test thoroughly!
-- devices (test UT, implement 340)
-- timing
+- improve timing
+- implement 340 display
+- do more tests