Threaded Mode | Linear Mode

Sylvain Cote · (This post was last modified: 10-10-2020 10:46 PM by Sylvain Cote.)

This is my solution for creating a custom FOCAL ROM on a DM41X using RAMBOX32 ROM and MLDL RAM (QROM).

Here are the reference modules: (in MOD format)

Simplified logic for a 4K ROM is:

Code:

{begin}

   {copy RAM-04K.MOD to MYROM01.MOD (or any other name)}

   {map MYROM01 module and note the page number, you will need it after}

   {map RAMBOX32 module}

   {begin rom}

      INITPG    {start building a ROM image in MLDL RAM}

      {begin program loading loop}

         LDPGM  {copy FOCAL program from main memory to MLDL RAM}

      {end program loading loop}

      ENDPG     {save ROM version, calculate checksum and save new checksum in MLDL RAM}

      ENDPG     {finish MLDL RAM writing session}

   {end rom, your FOCAL ROM is now done}

   {unmap RAMBOX32 module}

[end}

Example configuration:

Code:

RAMBOX32.MOD is mapped to page 8 (named "W&W RAMBOX 32"   in Active Modules list)

MYROM01.MOD  is mapped to page 9 (named "4K RAM for MLDL" in Active Modules list)

Sample code 1: (3 lines 11 bytes)

Code:

LBL "SND"

BEEP

END

Sample code 2: (4 lines 18 bytes)

Code:

LBL "DSP"

"MY ROM"

AVIEW

END

Init ROM image:

Code:

"-FOCAL APP1"     // ROM name

14                // XROM ID

9                 // page number

INITPG            // initialize MLDL RAM

CAT 2             // you should see "-FOCAL APP1" appears in the catalog

Load first program in ROM image:

Code:

FRYBT?            // free space available = 4044

"SND"

9

LDPGM             // load "SND" program in MLDL RAM at page 9

FRYBT?            // free space available = 4028  //  4044 - 11 (program) - 5 (probably header, I have to validate this) = 4028 ok

CAT 2             // you should see "-FOCAL APP1" and "SND"

CLP "SND"         // delete  "SND" program from main memory

XEQ "SND"         // execute "SND" program from MLDL RAM, you should hear the BEEP

Load second program in ROM image:

Code:

FRYBT?            // free space available = 4028

"DSP"

9

LDPGM             // load "DSP" program in MLDL RAM at page 9

FRYBT?            // free space available = 4005  //  4028 - 18 (program) - 5 (probably header, I have to validate this) = 4005 ok

CAT 2             // you should see "-FOCAL APP1", "SND" and "DSP"

CLP "DSP"         // delete  "DSP" program from main memory

XEQ "DSP"         // execute "DSP" program from MLDL RAM, you should see "MY ROM"

Close ROM image:

Code:

"FA1A"            // ROM version

9                 // page number

ENDPG             // will fail on first try, but needed to save ROM version, calculate checksum and save new checksum in MLDL RAM

ENDPG             // should succeed on the second try, MLDL RAM is now a ROM image.

Next step is to save the new ROM to the calculator file system.

press [shift] then SETUP
select: 2. Module >
select: 3. Save RAM Pages >
select: <New File>
enter: filename then press [R/S] to save the file

Remember, all RAM pages are saved in one big file.

Next, transfer the file to your computer.
I am still looking at how to convert the binary file to a mod file format.

Sylvain

Edit: adding saving RAM page information

PS: See my comment below.