L0D|Mr_B
New Member
hi all.
i'm redesigning my project for an "advanced" fan controller, using the 8051, and ive run into a brick wall :shock:
what i want to do is store commands in memory for a VFD (hard stored - not changeable, these are the commands to be passed to the VFD by my routines, it's for grfx, etc). what i want to do is something like :-
e.g.
LABEL data "this text is to be printed on the VFD"
e.g
DRAWBOX data 04,88,7F,90,94,00
.... where all the data is hex codes - a string - these would be predetermined commands for the VFD. question is, how do i access this data string, when i think the 8051 can only access DATA memory for data manipulation, not access program memory, where obviously this code sting for the VFD would reside.
i was going to add the strings in memory, then access them with a routine which would move along the string till it hit's a 00, where by the subroutine returns. my project was going to be PIC based, till i hit this, so going to 8051, plus i need more memory space (now can have 64K)
i know i could write something like :-
send "04"
send "88"
send "7f"
send .......
... but this would be both very wastefull and time consuming to code. i guess it comes down to "how do i load a register with a byte from program memory"
any ideas? can u think of another microcontroller which can be programmed via external eprom which has this facility, if it cant be done on the 8051?
B
i'm redesigning my project for an "advanced" fan controller, using the 8051, and ive run into a brick wall :shock:
what i want to do is store commands in memory for a VFD (hard stored - not changeable, these are the commands to be passed to the VFD by my routines, it's for grfx, etc). what i want to do is something like :-
e.g.
LABEL data "this text is to be printed on the VFD"
e.g
DRAWBOX data 04,88,7F,90,94,00
.... where all the data is hex codes - a string - these would be predetermined commands for the VFD. question is, how do i access this data string, when i think the 8051 can only access DATA memory for data manipulation, not access program memory, where obviously this code sting for the VFD would reside.
i was going to add the strings in memory, then access them with a routine which would move along the string till it hit's a 00, where by the subroutine returns. my project was going to be PIC based, till i hit this, so going to 8051, plus i need more memory space (now can have 64K)
i know i could write something like :-
send "04"
send "88"
send "7f"
send .......
... but this would be both very wastefull and time consuming to code. i guess it comes down to "how do i load a register with a byte from program memory"
any ideas? can u think of another microcontroller which can be programmed via external eprom which has this facility, if it cant be done on the 8051?
B