Re: Noob question: examine arbitrary memory address? #ELF #memory

Lee Hart

John Kennedy wrote:
Is it possible to examine the contents of an arbitrary memory address,
without pressing the IN button multiple times? I’d like to check if a
ROM I am programming is where I think it is - but pressing IN 32768
times seems a little tedious.
Hi John,

It's not hard to do, but how it's done depends on what Elf you are using.

If it's an 1802 Membership Card, the easy way is have the U2-LO jumper in place. That puts the ROM at address 0, so the front panel LOAD mode can easily read sequential locations starting at 0.

For other Elfs, you can figure out the address decoding to to the same; i.e. move the EPROM to 0.

Or, if you have RAM at 0 and the ROM is at 32768, you can write a little program that sets a register to 8000h (32768 decimal), and uses that register to read memory and display its contents. Then have each press of the IN button advance the address.

Lee Hart

A designer knows he has achieved perfection not when there is
nothing left to add, but when there is nothing left to take away.
-- Antoine de Saint Exupery
Lee Hart, 814 8th Ave N, Sartell MN 56377,

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