Hi All,

more or less I'm getting everything working in lazarus, I made a full working RC transmitter with PPM encoder, nrf24l01 and Nokia LCD. When ready I'll publish the project template and some units for everyone who wants to play with this.
Now the problem:
when trying to write or read
DMA1_Channel1.CCR:=0;
DMA1_Channel1.CNDTR:=0;
I get a window_watchdog_interrupt() in gdb and program stops running

while accessing these it's fine:
DMA1_Channel1.CPAR:=0;
DMA1_Channel1.CMAR:=0;

I modified the TDMA_Registers by removing the channel array and moved to the same implementation as stm stdlib do respecting the same absolute address but no way to get it working.

any suggestion?

Update:

I solved by declaring individual registers as absolute. I need the help of some fpc guru to understand why I got the problem.

According to stm32 manual I declared the same register in two ways: /
TDMAChannel = record
CCR,
CNDTR,
CPAR,

  CMAR :longword;

end;

DMA1_Channel1 : TDMAChannel                         absolute ($40020008);
dma1_ccr1 : longword   absolute($40020008);
dma1_cndtr1 : longword   absolute($4002000C);
dma1_cpar1 : longword   absolute($40020010);
dma1_cmar1 : longword   absolute($40020014);    /

I put some values to the serial port to understand what is happening:

/Serial1.println;
  Serial1.print('0x'+hexstr(longword(@DMA1_Channel1.CCR),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_CCR1),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_Channel1.CNDTR),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_CNDTR1),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_Channel1.CPAR),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_CPAR1),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_Channel1.CMAR),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_CMAR1),8));
  Serial1.println;   /

this is the output:
0x40020008 0x40020008 0x4002000C 0x4002000C 0x40020010 0x40020010 0x40020014 0x40020014

so address are exactly the same

if I remove the @ I should get the value of the register:

 / Serial1.println;
  Serial1.print('0x'+hexstr(longword(@DMA1_Channel1.CCR),8));
  Serial1.print(' 0x'+hexstr(longword(DMA1_CCR1),8));
  Serial1.print(' 0x'+hexstr(longword(@DMA1_Channel1.CNDTR),8));
  Serial1.print(' 0x'+hexstr(longword(DMA1_CNDTR1),8));
  Serial1.print(' 0x'+hexstr(longword(DMA1_Channel1.CPAR),8));
  Serial1.print(' 0x'+hexstr(longword(DMA1_CPAR1),8));
  Serial1.print(' 0x'+hexstr(longword(DMA1_Channel1.CMAR),8));
  Serial1.print(' 0x'+hexstr(longword(DMA1_CMAR1),8));
  Serial1.println;  /

this is the output:
0x40020008 0x00005A61 0x4002000C 0x0000000D 0x200002F4 0x200002F4 0x40010810 0x40010810

If I remove also the @ from /Serial1.print('
0x'+hexstr(longword(@DMA1_Channel1.CNDTR),8));/

this is the output:
0x40020008 0x00005A61

the program stops running when trying to access this register, it does the same with DMA1_Channel1.CCR.
what makes me mad is that the other 2 registers are well working and in the stm32f103fw unit there are a lot of registers which work fine with the record declaration.

Any idea?

Are you using 2.6.4? This sounds like something that was fixed some time ago in trunk.

Either way I cannot reproduce any problems with SVN trunk.

Thanks Jeppe, Solved!

it was a problem in the TDMAChannel declaration which I modified without rebuilding the fpc

here the produced asm code:

# [39] Serial1.print(' 0x'+hexstr(longword(DMA1_Channel1.CNDTR),8)); ldr r0,.Lj98
*ldrh r1,[r0]*
mov r2,#0
sub r0,r11,#560
mov r3,#8
bl SYSTEM_$$_HEXSTR$QWORD$BYTE$$SHORTSTRING
sub r3,r11,#560
ldr r2,.Lj84
sub r0,r11,#304
mov r1,#255
bl fpc_shortstr_concat
sub r1,r11,#304
ldr r0,.Lj25
ldr r0,[r0]
bl HWSERIAL$_$TSTM32SERIAL_$__$$_PRINT$SHORTSTRING # [40] Serial1.print(' 0x'+hexstr(longword(DMA1_CNDTR1),8)); ldr r0,.Lj98
*ldr r1,[r0]*
mov r2,#0
sub r0,r11,#560
mov r3,#8
bl SYSTEM_$$_HEXSTR$QWORD$BYTE$$SHORTSTRING
sub r3,r11,#560
ldr r2,.Lj84
sub r0,r11,#304
mov r1,#255
bl fpc_shortstr_concat
sub r1,r11,#304
ldr r0,.Lj25
ldr r0,[r0]
bl HWSERIAL$_$TSTM32SERIAL_$__$$_PRINT$SHORTSTRING

the only difference is the ldrh instruction which means halfword, in fact the original TDMAChannel declares CCR and CDNTR as word, changing them to longword and after rebuilding the fpc everything is working with channel array!