Re: [N8VEM-S100:4164] Multiple Rom Monitors and a conflict

Hi Thomas,

I've just picked up your post,

I think you are onto the issue already but I'll explain how my setup is done.

the Z80 monitor is a 8K chip arranged in two pages (4k each) that reside at address F000H to FFFFH (as per S100 Z80 Master CPU documentation)

the MYIDE rom is still an 8K chip and should logically be placed on an 8k boundry to avoid overlap with the existing monitor, but what I did on my

S100 computers RAM/ROM board was to arrange for the ROM base address to be E0000H, place the code in the lower 4K section of the chip, and used the phantom line to mask off the upper 4K. This allowed me to free up a little more freespace ram.

If you dont have this facility on your board then you will need to set the ORG statement in the MYIDEROM code and recompile it to run in a different location in memory.

regards

David Fry
On Saturday, June 14, 2014 12:32:29 AM UTC+1, Thomas Owen wrote:

Hello Everyone,
I should have been a little more clear with my statements...
I install the rom, either one, in my Ram17 board by simply removing ram chips. So, either one will work installed by itself in the system.
I can access all functions of both roms just fine.
It is when they are both installed in the system together, one at e000 (myiderom) and the other at F000 (masterz80) that neither will work.
I start the system, reset, and try to run from either start address and the system just hangs.
I think John is on to the problem as i believe they both are trying to use space occupied by the other rom, thinking it is ram.
What I need to do is set the top of ram below the rom at E000 (I think!) within each rom.
Summary:
Masterz80:
Ram 0 - EFFF Rom at F000. This works fine.
Myiderom:
Ram 0 - DFFF, rom at E000. This works fine.
Masterzz80 and myiderom together in system:
Ram 0 - DFFF, Myiderom at E000 to EFFF, Masterz80 at F000 to,FFFF. System simply hangs trying to launch either rom.
Thanks again,
Thomas