ees@vax135.UUCP (Gene Sampieri) (08/03/84)
The following is a discription of the 99/4a CONSOLE GROM. There
are 3 chips each containing 6K bytes, each resident within the
8K area from >0000 to >17ff. These chips are paged by the operating
system and contain both programming and data.
GROM 0 >0000 - >17ff The title screen and power-up routine,
title screen character set, standard character set,
lower case character set, hi-level cassette DSR messages
and the trig functions such as ATN,SIN etc.
GROM 1 >2000 - >37ff Vector tables for the Basic language, the error
statements for Basic and part of the Basic interpreter.
GROM 2 >4000 - 57ff Part of the Basic interpreter, the reserved word
list and their associated token values.
There are 4 chips, GROM 3 - 6, for a total of 24K, that reside in the
Extended Basic cartridge.
GROM 3 >6000 - >77ff XBASIC vector tables, error statements and part
of the XBASIC interpreter.
GROM 4 >8000 - >97ff More of the XBASIC interpreter.
GROM 5 >a000 - >b7ff More of the XBASIC interpreter.
GROM 6 >c000 - >d7ff The rest of the XBASIC interpreter, the reserved
word list and their associated token values.
Since the groms are only 6K, there is 2K wasted between each
8K block.
The next chart shows the memory allocation as you add options. It is
broken into two areas, one for ROM-GROM and the other is RAM.
CONSOLE MEMORY
8K CONSOLE ROM - >0000 - 1FFF 8K CONCOLE RAM - >8000 - 9FFF
18K CONSOLE GROM - >0000 - 5800 * 16K VDP RAM - >0000 - 3FFF *
------------------------------- ------------------------------
26K ROM/GROM TOTAL 24K OF RAM TOTAL
CONSOLE MEMORY PLUS EXTENDED BASIC
8K CONSOLE ROM - >0000 - 1FFF
12K X-BASIC ROM - >6000 - 7FFF
18K CONSOLE GROM - >0000 - 57FF * 8K CONSOLE RAM - >8000 - 9FFF
24K X-BASIC GROM - >6000 - D7FF * 16K VDP RAM - >0000 - 3FFF *
------------------------------ ------------------------------
62K OF ROM/GROM TOTAL 24K OF RAM TOTAL
add the.. MEMORY EAPANSION AND THE SPEECH SYNTHESIZER
8K CONSOLE ROM - >0000 - 1FFF
12K X-BASIC ROM - >6000 - 7FFF 8K EXPAN RAM - >2000 - 3FFF
18K CONSOLE GROM - >0000 - 57FF * 8K CONSOLE RAM - >8000 - 9FFF
24K X-BASIC GROM - >6000 - D7FF * 24K EXPAN RAM - >A000 - FFFF
32K SPEECH ROM - >0000 - 7FFF * 16K VDP RAM - >0000 - 3FFF *
------------------------------- ------------------------------
94K OF ROM/GROM TOTAL 56K OF ROM/GROM TOTAL
then add.. THE RS232 CARD AND THE DISK CONTROLLER CARD
8K CONSOLE ROM - >0000 - 1FFF
2K RS232 DSR ROM- >4000 - 4800 (APROX)
8K DISK DSR ROM - >4000 - 5FFF
12K X-BASIC ROM - >6000 - 7FFF 8K EXPAN RAM - >2000 - 3FFF
18K CONSOLE GROM - >0000 - 57FF * 8K CONSOLE RAM - >8000 - 9FFF
24K X-BASIC GROM - >6000 - D7FF * 24K EXPAN RAM - >A000 - FFFF
32K SPEECH ROM - >0000 - 7FFF * 16K VDP RAM - >0000 - 3FFF *
------------------------------- ------------------------------
104K ROM/GROM TOTAL 56K RON/GROM TOTAL
* These are memory mapped devices. You cannot PEEK or here from XBASIC.