Weird mapper

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Weird mapper
by on (#71976)
My brother gave me one of these Gold Leopard King computers based on NOACs (I like a lot these weird consoles)

Well, I was playing with the "G BASIC" included trying to find the mapper (using POKEs over all the ROM space). I discovered the following:

Offset $C800 bit 1:
Freezes console when set. Other bits does nothing

Offset $C801:
$01, $08, $09, $10, $11: Black screen and glitchy menu after pressing ENTER (but impossible to enter nowhere, clicking anywhere restarts the menu over and over)
$02, $03, $0A, $0B, $12: Does nothing (BASIC says "OK")
$04, $05, $0C, $0D: opens ENGLISH EDIT (text editor)
$06, $07, $0E, $0F Freezes console
Other values untested

Offset $C802 bit 0/1:
Freezes console when set. Other bits does nothing

There are NO mirrors anywhere

What type of Mapper could be this? I read SUBOR mapper was very simple: http://wiki.nesdev.com/w/index.php/SUBOR , so I don't know why this is so complex, and why uses $C80x instead of simpler ways other mappers uses

PS: I used the following code to search for special addresses:
Code:
10 CNT=16
20 ADDR=&H8000
30 IF CNT<16 THEN GOTO 60
40 PRINT HEX$(ADDR)
50 CNT=0
60 POKE ADDR, &HAA
70 POKE ADDR, &H55
80 IF ADDR=&HFFFF THEN END
90 ADDR=ADDR+1
100 CNT=CNT+1
110 GOTO 30


PS 2: That damn BASIC shows 31568 bytes of available memory but using more than 200 bytes overflows and corrupts the BASIC program :evil:

by on (#71977)
Like many of the Chinese 'computers', it likely uses a custom mapper. Kevtris or Tepples may be able to provide better insights. What are you trying to achieve, may I ask?

by on (#71978)
First I were trying to discover if it has internal RAM to store data on the Family Basic (G BASIC). Then I found that no, it doesn't (manually dumped each byte of data from the RAM and found my code on it, so think it doesn't)

And now I want to dump the cartridge to search for G BASIC commands (there are no manuals anywhere, so I want to dump it and analyse its tokens)