From 7473adafeb4f0a424c7bd2acb1dee869cd164e0c Mon Sep 17 00:00:00 2001 From: Madeline Cronin Date: Mon, 26 Aug 2024 22:36:34 +0100 Subject: [PATCH] Remove the 512 word copy behaviour and change references to RAM The removal is because the copy behaviour would be better placed in a platform architecture the references to RAM are changed to be "main memory" so that a platform architecture can use different blocks of main memory for different purposes. --- ISA_spec.txt | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/ISA_spec.txt b/ISA_spec.txt index 7033351..1200bd1 100644 --- a/ISA_spec.txt +++ b/ISA_spec.txt @@ -1,4 +1,4 @@ -Maddie's test ISA Version 1.0.2 +Maddie's test ISA Version 1.0.3 Table of contents: @@ -22,8 +22,7 @@ counter, and interrupt register. The program counter is freely readable, but only modifiable through instructions in the control flow category. There is also a 2 bit flags register for storing the condition flags. -Behaviours: Upon power up, the first 512 words of disk are copied to main -memory. The only statefulness not directly controlled by programs is the +Behaviours: The only statefulness not directly controlled by programs is the interrupt toggle. Numbers are read as big endian. Hardware interrupts jump to zero, and push the prior program counter to the stack. @@ -121,7 +120,7 @@ A: (A=0) Read/pop, (A=1) Write/push XXX= 000: Pop/push to stack -001: Read/write RAM +001: Read/write main memory 010: R/W disk 011: R/W VRAM 100: R/W to serial port -- 2.43.4