I opened the file and saw something a bit strange:
Code: Select all
START LDU BADDR
LEAX FORPAR,PCR
NA3 CLRB
LOOP1 LDD ,X++
STA 1,U
STB ,U
INCB
CMPB #6
BCS LOOP1
It is strange to use the register B as a Loop control when we are using the register D to load data from the table FORPAR, so B gets modified inside the loop.
Thanks God, it does four loops and then breaks because B is assigned value $80 (greater than $06), so the CURLO and CURHI are not configured.
I assume that by defaut their value is $00.
By now I'm reading and re-reading the CRT9128 datasheet to understand what is it able to do and hope this will help me understand what Luis has coded in that drive.
I am retyping the driver on DskDream little by little, testing step by step to figure out how it works.
By the way, I have noticed that if I type on the Dragon normal screen EXEC&H7D04 another time, then the computer hangs and Reset doesn't bring it back to life, so I need to stop the Dragon and restart again
regards
pere