G'mon 6502

G'mon (the Generic Monitor) is a machine monitor based around being small and easy to add to. Currently, with BASIC included, it sits right under 2KB in size.

Summary of content

G'mon-6502 includes my monitor as well as a version of TinyBasic that i have transcoded to assemble with KickAssembler The commands currently implemented in G'mon 6502:

• Enter (CR) | [HHHH] {Return} - Hex dump address
• . | [HHHH][.HHHH] {Return} - Hex dump address range
• : | [HHHH][:DD] {Return} - Poke data
• g - Go | [HHHH][G] {Return} - Run a program
• v - Version | [V] {Return} - Print version string
• t - Text Dump | [HHHH][T][XXXX] {Return} - Dump text string XXXX into memory location HHHH
• x - Read text from memory | [HHHH][X}[-X] {Return} - Print text string located at HHHH until a CR is printed (X = Number of times to continue after a CR is reached)
• z - Convert bases | [HH][Z][-{I}{O}] - Convert a number (HH) to a different base (Option is H-Hex D-Decimal B-Binary, I=Input Base, O=Output Base)

Usage

To compile G'mon-6502 for a given system, first edit Configuration.asm. Variables that will likely need to be changed:

• RomStart
• RomSize
• Clock

There are also config statements for a few things like boot messages and such. Here you can also enable/disable TinyBasic.

Once that has been changed, replace the Write and Read functions in Kernal.asm with ones specific to your hardware

Now edit the Makefile to specify the command you use to run KickAssembler. To build, enter the ./src/ directory and run make to generate ROM.bin.

The generated ROM can currently be used in Symon, a 6502 simulator (so long as Emulated = true). Otherwise, just burn the ROM to an EEPROM and use it in your system!

Links

• TinyBasic - GitHub Repository

Contributing

Please read CONTRIBUTING.md for info about contributing to G'mon-6502.

Authors

• Carson Herrington / NotArtyom - All Code - Website