Fixed Point Basic

Default the VIP emulator will start up with Fixed Point Basic (FPB) loaded. In this configuration the VIP is started with 7 VP570 boards, i.e. 32 KB RAM as well as the VP590 colour board and of course ASCII keyboard support.

Three versions of FPB are included in Emma 02:

fbb.bin: original FPB
fpb_color.bin: colour version of FPB
fpb_color_skip_loader.bin: same as above but skipping the boot loader

All files include the (original) boot loader from 0 to FF. The bootloader is also included as a stand alone file (fpb_bootloader.bin). On startup the VIP will run the bootloader where:

Key 1: Jump directly to FPB.
Hold 'B' while switching to 'RUN' (F12): "Tape Read", this isn't needed in Emma 02 as FPB is already loaded via the fpb.bin or fpb_color.bin file.
hold 'F' while switching to 'RUN' (F12): "Tape Write", allows user to make a copy of FPB hex 100-3FFF.

When using the fpb_color_skip_loader.bin version FPB will skip the bootloader on startup this was done by changing the following bytes:

Original:	Mod:    
0008: 62	0008: 30
0009: 0B	0009: 1A
0012: 62	0012: 30
0013: 01	0013: 1A

FPB only allows 32K of RAM (Due to the VIP ROM using all addresses above hex 8000). The bootloader included is set to 32K. If you would like to use less RAM you need to alter the following addresses in the fpb-rom and/or fpb_color.rom files:

hex 1C - High byte of available RAM size (hex 7F for 32K)
hex 1F - Low  byte of available RAM size (hex FF for 32K)