01 /*
02  * nvdata.c
03  *
04  *  Created on: 19 Mar 2021
05  *      Author: andrew
06  */
07
08 #include "main.h"
09
10 extern uint32_t _nvdata[1024]; // start of non-volatile data (last block of main flash) defined in linker file
11
12 /** */
13 void NVDATA_SaveCalibrationParams(uint32_t span, uint32_t zero)
14 {
15   HAL_FLASH_Unlock();
16
17   FLASH_EraseInitTypeDef eraseInit;
18
19   eraseInit.TypeErase = FLASH_TYPEERASE_PAGES;
20   eraseInit.NbPages = 1;
21   eraseInit.PageAddress = (uint32_t)&_nvdata[0];
22
23   uint32_t sectorError;
24   printf("erasing flash page at %p\n", &_nvdata[0]);
25   HAL_StatusTypeDef res = HAL_FLASHEx_Erase(&eraseInit, &sectorError);
26
27   if (res != HAL_OK)
28   {
29     printf("FLASH erase error %d\n", res);
30   }
31
32   res = HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, (uint32_t)&_nvdata[0], span);
33
34   if (res != HAL_OK)
35   {
36     printf("FLASH program error %d\n", res);
37   }
38
39   res = HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, (uint32_t)&_nvdata[1], zero);
40
41   if (res != HAL_OK)
42   {
43     printf("FLASH program error %d\n", res);
44   }
45
46   HAL_FLASH_Lock();
47 }
48
49 /** */
50 void NVDATA_LoadCalibrationParams(uint32_t *span, uint32_t *zero)
51 {
52   *span = _nvdata[0];
53   *zero = _nvdata[1];
54 }

01 /* Entry Point */
02 ENTRY(Reset_Handler)
03
04 /* Highest address of the user mode stack */
05 _estack = ORIGIN(RAM) + LENGTH(RAM);  /* end of "RAM" Ram type memory */
06 _nvdata = ORIGIN(NVDATA);
07
08 _Min_Heap_Size = 0x200 ;  /* required amount of heap  */
09 _Min_Stack_Size = 0x400 ; /* required amount of stack */
10
11 /* Memories definition */
12 MEMORY
13 {
14   RAM    (xrw)    : ORIGIN = 0x20000000,  LENGTH = 4K
15   FLASH  (rx)     : ORIGIN = 0x8000000,   LENGTH = 15K //reduce flash by 1K
16   NVDATA (rx)     : ORIGIN = 0x8003c00,   LENGTH = 1K //define the nv region
17 }
18
19 /* Sections */
20 SECTIONS
21 {
22  ### ommited ###
23
24   .nvdata : // give the nv region a name so it can be referenced from code
25   {
26     KEEP(*(.nvdata))
27   } >NVDATA
28
29  ### ommited ###
30 }

01 int32_t zero = 0;
02 int32_t span = 1;
03
04 // main acquisition loop
05 while (true)
06 {
07   // get averaged data here
08
09   if (sw1PushedEvent())
10   {
11     zero = average;
12     NVDATA_SaveCalibrationParams(span, zero);
13   }
14
15   if (sw2PushedEvent())
16   {
17     raw = (average - zero) * 100;
18
19     span = raw / 1000;
20
21     NVDATA_SaveCalibrationParams(span, zero);
22   }
23
24   display = ((average * 100 - zero * 100) / span);
25
26   LCD_PrintNumber(display, 0);
27 }