Add support for SH1106 OLED display driver

+ associated example/demo code

Author: jpcornil-git

examples/board_sh1106/Makefile

@@ -0,0 +1,49 @@
+# 
+# 	Copyright 2008-2011 Michel Pollet <buserror@gmail.com>
+#
+#	This file is part of simavr.
+#
+#	simavr is free software: you can redistribute it and/or modify
+#	it under the terms of the GNU General Public License as published by
+#	the Free Software Foundation, either version 3 of the License, or
+#	(at your option) any later version.
+#
+#	simavr is distributed in the hope that it will be useful,
+#	but WITHOUT ANY WARRANTY; without even the implied warranty of
+#	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#	GNU General Public License for more details.
+#
+#	You should have received a copy of the GNU General Public License
+#	along with simavr.  If not, see <http://www.gnu.org/licenses/>.
+
+target=	sh1106demo
+simavr = ../../
+
+IPATH = .
+IPATH += ../parts
+IPATH += ${simavr}/include
+IPATH += ${simavr}/simavr/sim
+
+VPATH = .
+VPATH += ../parts
+
+LDFLAGS += -lpthread
+
+include ../Makefile.opengl
+
+all: obj ${target}
+
+include ${simavr}/Makefile.common
+
+board = ${OBJ}/${target}.elf
+
+${board} : ${OBJ}/sh1106_virt.o
+${board} : ${OBJ}/sh1106_glut.o
+${board} : ${OBJ}/button.o
+${board} : ${OBJ}/${target}.o
+
+${target}: ${board}
+	@echo $@ done
+
+clean: clean-${OBJ}
+	rm -rf *.hex *.a *.axf ${target} *.vcd .*.swo .*.swp .*.swm .*.swn

examples/board_sh1106/README.md

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+# SH1106 OLED demo (navigation menu for a motor controller)
+
+See detailed description of the emulated system here https://github.com/jpcornil-git/Cone2Hank
+
+- Use arrows to navigate menu
+- \<enter\> to select
+- \<space\> to start,pause or stop (long press) motor
+- 'v' to start/stop VCD traces
+- 'q' or ESC to quit
+
+**NOTE**: Emulation may be slightly slower than realtime and a keypress has to be long enough to cope with that.
+
+## Usage
+Command line options:
+```
+$ sh1106demo.elf --help
+Usage: sh1106demo.elf [...] <firmware>
+       [--help|-h|-?]      Display this usage message and exit
+       [--list-cores]      List all supported AVR cores and exit
+       [-v]                Raise verbosity level
+                           (can be passed more than once)
+       [--freq|-f <freq>]  Sets the frequency for an .hex firmware
+       [--mcu|-m <device>] Sets the MCU type for an .hex firmware
+       [--gdb|-g [<port>]] Listen for gdb connection on <port> (default 1234)
+       [--output|-o <file>] VCD file to save signal traces (default gtkwave_trace.vcd)
+       [--start-vcd|-s     Start VCD output from reset
+       [--pc-trace|-p      Add PC to VCD traces
+       [--add-trace|-at <name=[portpin|irq|trace]@addr/mask or [sram8|sram16]@addr>]
+                           Add signal to be included in VCD output
+       <firmware>          An ELF file (can include debugging syms)
+```
+## Examples
+### Execute firmware.elf (with no .mmcu section -> -m and -f required) on system
+```
+$ sh1106demo.elf -m atmega32u4 -f 16000000 firmware_no_mmcu.elf
+```
+        
+### Start system and wait for gdb to connect, load firmware, ...
+```
+$ sh1106demo.elf -m atmega32u4 -f 16000000 -g
+```
+
+### Execute firmware.elf on system and trace signals in a VCD file
+- .mmcu section of the firmware includes something like:
+  ```
+  #include "avr_mcu_section.h"
+  
+  extern void *__brkval;
+  
+  AVR_MCU (F_CPU, "atmega32u4" );
+  AVR_MCU_VOLTAGES(3300, 3300, 3300);
+  AVR_MCU_VCD_FILE("simavr.vcd", 10000000);
+  
+  const struct avr_mmcu_vcd_trace_t _mytrace[]  _MMCU_ = {
+    { AVR_MCU_VCD_SYMBOL("Encoder"), .what = (void*) &PIND, .mask=(1<<PIND2), },
+  	{ AVR_MCU_VCD_SRAM_16("Heap"), .what = (void*)(&__brkval), },
+  };
+  ```
+- Options from the command line:
+  - Add a 16 bits trace for Stack Pointer (SPL/SPH)  (could also be in the section above)
+  - Add a (16 bits) trace for Program Counter (PC)
+  - Start VCD dump (set to "simavr.vcd" in the .mmcu section) from reset
+```
+$ sh1106demo.elf --add-trace Stack=sram16@0x5d -p -s firmware_mmcu.elf 
+```
+  GTKWave ouput
+
+![PS_SP-Heap_3x](https://github.com/jpcornil-git/simavr/assets/40644331/b4cefeb2-e33f-4c21-afa6-2b15b92eed37)