User guide

The default base address, &E000, was chosen because it is the start point of the Amélie EPROM.
If this address is not suitable, you can easily do something like:
ROM
BOT &A000 FORCE
ORG &A000
TOP <address>
This specifies the higher address of the assembly. If no address is specified, the address after the
last instruction assembled is assumed...
...unless the ROM command has been previously specified, in which case &FFFF will be assumed.
Once TOP has been set, you cannot reTOP to a lower address. This is important as you cannot use
the ROM command to set up an arbitrary EPROM environment for, say, BBC paged ROMs. An
example of how to do this would be something like:
BOT &8000 ; set the bottom
ORG &8000 ; go there
FIL &3FFF, &FF ; fill the area with &FF bytes
TOP &BFFF ; affirm the end location
ORG &8000 ; back to the beginning
; code follows, i.e.:
DCW entrypoint_language
DCW entrypoint_service
DCB %11100010 [...etc...]
It is important to note that the values set by the BOT, ROM, and TOP commands directly relate to the range
saved in the output file.
For example:
BOT &0000
TOP &FFFF
will cause 65,535 bytes (64K) to be saved to file.
BOT &F000
INX
will cause one byte to be saved to file.
ROM
will cause 8192 bytes to be saved to file.
6502asm user guide – prerelease version
page 9