S12 / MagniV MicrocontrollersのトピックRe: S12G128 P-Flash reading issue in bootloader

S12G128 P-Flash reading issue in bootloader

walter_wang — Thu, 02 Mar 2017 01:20:36 GMT

Dears,

I'm working on S12G128 bootloader, it is based on AN4258.

Some certain chars have been written to P-Flash global address 0x2FE00, so after reset, bootloader will read address 0x2FE00 and decide how to go. A far pointer Upg_Cmd defined for this operation. See below code for more details.

#define Upg_Cmd_Addr 0x2FE00 //Global address 0x2FE00, store the chars

UINT8 * far Upg_Cmd;

#define GlobalToLocal(Address) (((Address) & 0x3FFFU) | (((Address) & 0x003FC000UL) << 2U) | 0x8000U)

UINT8 cc;

UINT8 const far upg_cmd_array[] @0x0BBE00 = "54600856"; //For debugging, test if bootloader can read these chars.

In main program, I'm using Upg_Cmd pointer to get the content in 0x2FE00 (Local paged address 0xBBE00) but always get 0xFF. I checked in BDM debugger interface and the actual content of 0x2FE00 (Local paged address 0xBBE00) is correct and not corrupted, also, Upg_Cmd can be correctly assigned 0xBBE00.

Upg_Cmd= (UINT8 * far) GlobalToLocal(Upg_Cmd_Addr);

cc= *Upg_Cmd++;

When code executed, cc is 0xFF which suppose to be '5'.

Any hints are apppreciated.

Walter

Re: S12G128 P-Flash reading issue in bootloader

lama — Thu, 02 Mar 2017 11:33:33 GMT

Hi,

see attached example project and read the main.c file:

//------------------------------------------------------------------------------
// for space creation see prm file. Search for keyword "NXP support"
// the cons is also added into entries and added feature "volatile" to be sure
//    it is not revomed by optimization. You should check the address in debugger
//    or S19 record to be sure the data is there
// Be sure you are using correct routine to get data from flash :
//     press Alt F7-> Compiler for HCS12 -> Options -> Code generation ->
//           -> Match PPAGE register is used for paging
//     Write Runtime in the cell which appears.
//   ..or write -CpPPAGE=RUNTIME into compiler option

// The compiler command line is also adjusted to be compiler informed we will
// use paged variables. The option "-D__FAR_DATA" is added into
// the compiler command line (Alt F7->Compiler for HC12 ->
// ->Add -D__FAR_DATA in the Command Line Arguments)

//------------------------------------------------------------------------------

..or write -CpPPAGE=RUNTIME into compiler option…

When debug you use see:

I hope this will lead you to solve your issue.

Best regards,

Ladislav

Re: S12G128 P-Flash reading issue in bootloader

walter_wang — Thu, 02 Mar 2017 13:09:07 GMT

Hi Iama,

Thanks for reply, unfortunately my issue still remains the same after adding these compilor options.

But when I'm trying debugging into assembly codes, especially going through the routine _LOAD_FAR_8, the root cause seems found:

The problem may be caused by wrong PPAGE address defined in datapage.c, it was defined 0x30 as below picture shows, but S12G128 PPAGE register is at 0x15.

This bug in AN4258 based bootloader may cause codes cannot use "* far" or "*__far" to read banked data due to wrong PPAGE address.

After modifying PPAGE_ADDR to correct address 0x15, data at Flash address 0x20000 (banked addr is 0xBBE00) can be read correctly.

Thanks for your support, and it would be good if you can add this finding to AN4258 new revision.

Walter

Re: S12G128 P-Flash reading issue in bootloader

lama — Fri, 03 Mar 2017 07:51:03 GMT

Hi,

which version of the CW you use? (No IDE version but CW4.1, 4.2,.5.0, 5.1, 5.2)

Could you please send me your project? You can use standard "support" way to nxp - just introduce email by hello Ladislav. (https://community.nxp.com/docs/DOC-329745 )

However, it would be better if you are able to send shortened, fuctional, issue highlighting version of the project.

(Do not forget to pack entire project. I hope you have set the project paths relative to project. The best is if everything is placed in the project folder)

Or you can send it to hcs12@seznam.cz.

I'll check and correct it.

Best regards,

Ladislav

Re: S12G128 P-Flash reading issue in bootloader

walter_wang — Tue, 18 Apr 2017 08:55:49 GMT

Hi Lasislav,

I'm using CW 5.1. We have done a lot of changes to bootloader to fit our application. Really sorry that I cannot send it due to RD policy.

The issue is really simple and clear: the PPAGE_ADDR definition in datapage.c is not correct. Also, it is easy to re-produce, by just define a __far array in main.c and try to read it.

Thanks

Walter.