Things that remain constant whichever Mbed LPC1768 is used: peripheral definitions; leds; memory layout; main processor clock. Note that watchdog, default and hard fault handlers; peripheral power and clocks; and the vector table will need to be set up for each project.
Dependents: test-lpc1768 oldheating gps motorhome ... more
Aim
To program the MBED LPC1768 using just the online compiler and the UM10360.pdf manual.
As a hobbyist I want to do the fun stuff - programming the various peripherals to make them do what I wanted them to do - unfortunately the Mbed OS libraries have done all that while leaving the mundane for me to do.
The Mbed OS libraries have to cope with multiple compilers, multiple targets and all the peripherals even if not used; making them large and putting many layers between you and the registers of the LPC1768.
We, on he other hand, can limit ourselves to a single compiler (the online ARM CC compiler), one target (the MBED LPC1768), and those few peripherals we need which, together with limiting some abilities such as dynamic allocation of interrupt vectors, allows us to dramatically reduces the number of files required and means we can specify and understand each and every bit of our application.
Technical
Bit Banding
Use bit-banding to access the individual bits by mapping each bit in the region base (GPIO 0x2000 0000 or peripheral 0x4000 0000) to a word in the region alias (GPIO 0x2200 0000 or peripheral 0x4200 0000).
The formula is therefore ALIAS + ((((registerAddress - BASE) << 3) + BIT) << 2))
which calculates the number of bits above the base [bytes * 8 plus bit number]; converts it to the number of bytes [ *4] and adds that to the alias.
Writing with bit banding still involves a read modify write cycle; the difference is that the cycle and bit twiddling is managed in hardware and is atomic.
For GPIO writes it is better to use the SET and CLR registers without bit banding to eliminate the surplus read.
Startup code
From the ARM Information Center:
__main
calls__scatterload
then calls__rt_entry
__scatterload
goes through the region table and initializes the various execution-time regions__rt_entry
calls__user_setup_stackheap
to initialise the stack and heap, then calls__rt_lib_init
to initialise the C library sub systems and finally calls the user-levelmain
Files used
These are the files listed roughly in the order you might create them.
Files you would not normally touch are in the lpc1768 library to make them easier to maintain, while files you would normally modify to suit your application are in the main folder.
lpc1768 contains static files for:
- startup - memory layout in a scatter file and a routine to calculate the stack and heap locations
- bitband - macros for each of the two bit band regions
- system - set up the PLL to take the CPU clock from 12 to 96MHz
- gpio - addresses of the various GPIO registers
- led - leds 1 to 4: get, toggle and set
- serialpc - the serial link to the PC using uart0
- firmware - contains routines to handle the uploading of new firmware without having to plug into the usb port
- semihost - contains routines to do various jobs such as MAC, reset and local file handling
- fault - saves the location of a fault across restarts in a small area left aside in the scatter file
- handlers - hard fault and default handlers: other handlers are defined in the module that uses them
- watchdog - watchdog handler
main contains files to modify for:
- vectors - a simple list of handler addresses without any code
- periphs - a list of peripherals to power up and their clock dividers
- main - the start up routine which calls periphs, system, and led initialisation then loops flashing an led
startup.sct
Contains the scatter file where the different memory regions are defined for the linker.
Derived from targets/TARGET_NXP/TARGET_LPC176X/device/TOOLCHAIN_ARM_STD/LPC1768.sct.
I have removed the NIVT and IAP reserved areas by not moving the vector table into ram (therefore have to specify the handlers at link time: they cannot be dynamically allocated) and by not using In Application Programming.
The .CRPSection
, together with a line in startup.c ensures that the value -1 is stored in location 0x2FC thereby setting code read protection to none.
The following sections are specified:
RESET
- used in vectors.S.CRPSection
- used in startup.c to ensure that Code Read Protection is set to noneInRoot$$Sections
- used for code which must execute at its load addressAHBSRAM0
- used in the log module for use as buffer; normally dedicated to USB if you use itAHBSRAM1
- used in the net module for the ethernet buffersfault
- Leave 4 bytes for the fault code at 20083FFCCANRAM
- normally dedicated to Controller Area Network if you use it
startup.sct
#! armcc -E #define MBED_APP_START 0x00000000 #define MBED_APP_SIZE 0x80000 LR_IROM1 MBED_APP_START MBED_APP_SIZE ; load region size_region { ER_IROM0 MBED_APP_START 0x2FC ; load address = execution address { *.o (RESET, +First) .ANY (+RO) } ER_CRP (MBED_APP_START + 0x2FC) FIXED 4 { *.o (.CRPSection) } ER_IROM1 (MBED_APP_START + (0x2FC + 4)) FIXED (MBED_APP_SIZE - (0x2FC + 4)) { *(InRoot$$Sections) .ANY (+RO) } RW_IRAM1 0x10000000 0x8000 ; RW and ZI { .ANY (+RW +ZI) } RW_IRAM2 0x2007C000 0x4000 ; RW data, USB RAM used by the Log module { .ANY (AHBSRAM0) } RW_IRAM3 0x20080000 0x3FFC ; RW data, ETH RAM used by the Net module. Leave 4 bytes for the fault code at 20083FFC { .ANY (AHBSRAM1) } RW_IRAM4 0x40038000 0x0800 ; RW data, CAN RAM { .ANY (CANRAM) } }
startup.c
Contains the c function __user_setup_stackheap
which is called from __main
to calculate the stack and heap positions prior to main
being called .
Derived from platform/mbed_retarget.cpp.
startup.c
#include <stdint.h> #include <rt_misc.h> __attribute__ ((section (".CRPSection"), used)) const long crpKey = -1; //Don't use Code Read Protection extern char Image$$RW_IRAM1$$ZI$$Limit[]; __value_in_regs struct __initial_stackheap __user_setup_stackheap(uint32_t R0, uint32_t R1, uint32_t R2, uint32_t R3) { uint32_t zi_limit = (uint32_t)Image$$RW_IRAM1$$ZI$$Limit; uint32_t sp_limit = __current_sp(); zi_limit = (zi_limit + 7) & ~0x7; // ensure zi_limit is 8-byte aligned struct __initial_stackheap r; r.heap_base = zi_limit; r.heap_limit = sp_limit; return r; }
vectors.S
Contains the vector table specified in assembly; there is no code here: just pointers
Derived from targets/TARGET_NXP/TARGET_LPC176X/device/TOOLCHAIN_ARM_STD/startup_LPC17xx.S.
There are two difference from Mbed:
- I have not specified a
ResetHandler
orSystemInit
function but have just put__main
directly into the table and calledSystemInit
frommain
: there is no longer assembly code for a reset handler which callsSystemInit
then__main
. - I define the handlers in the module they are used (the default and hard fault handlers have been given their own module) and put the name directly into the table: they are no longer weak references which default to an infinite loop if not defined.
To define an interrupt handler in a given application:
- Define the handler (void parameters and returns void) in its module using the attribute
__irq
- Add the name of the handler to the list of IMPORTs
- Replace 'DefaultHandler' on the relevant line of __Vectors with the name of the handler
vectors.S
__initial_sp EQU 0x10008000 ; Top of RAM from LPC1768 PRESERVE8 THUMB ; Vector Table Mapped to Address 0 at Reset AREA RESET, DATA, READONLY EXPORT __Vectors IMPORT __main IMPORT DefaultHandler IMPORT HardFaultHandler IMPORT WatchdogHandler __Vectors DCD __initial_sp ; Top of Stack DCD __main ; Reset Handler DCD DefaultHandler ; NMI Handler DCD HardFaultHandler ; Hard Fault Handler DCD DefaultHandler ; MPU Fault Handler DCD DefaultHandler ; Bus Fault Handler DCD DefaultHandler ; Usage Fault Handler DCD 0 ; Reserved DCD 0 ; Reserved DCD 0 ; Reserved DCD 0 ; Reserved DCD DefaultHandler ; SVCall Handler DCD DefaultHandler ; Debug Monitor Handler DCD 0 ; Reserved DCD DefaultHandler ; PendSV Handler DCD DefaultHandler ; SysTick Handler ; External Interrupts DCD WatchdogHandler ; Watchdog Timer DCD DefaultHandler ; Timer0 DCD DefaultHandler ; Timer1 DCD DefaultHandler ; Timer2 DCD DefaultHandler ; Timer3 DCD DefaultHandler ; UART0 DCD DefaultHandler ; UART1 DCD DefaultHandler ; UART2 DCD DefaultHandler ; UART3 DCD DefaultHandler ; PWM1 DCD DefaultHandler ; I2C0 DCD DefaultHandler ; I2C1 DCD DefaultHandler ; I2C2 DCD DefaultHandler ; SPI DCD DefaultHandler ; SSP0 DCD DefaultHandler ; SSP1 DCD DefaultHandler ; PLL0 Lock (Main PLL) DCD DefaultHandler ; Real Time Clock DCD DefaultHandler ; External Interrupt 0 DCD DefaultHandler ; External Interrupt 1 DCD DefaultHandler ; External Interrupt 2 DCD DefaultHandler ; External Interrupt 3 DCD DefaultHandler ; A/D Converter DCD DefaultHandler ; Brown-Out Detect DCD DefaultHandler ; USB DCD DefaultHandler ; CAN DCD DefaultHandler ; General Purpose DMA DCD DefaultHandler ; I2S DCD DefaultHandler ; Ethernet DCD DefaultHandler ; Repetitive Interrupt Timer DCD DefaultHandler ; Motor Control PWM DCD DefaultHandler ; Quadrature Encoder Interface DCD DefaultHandler ; PLL1 Lock (USB PLL) ALIGN END
bitband.h
bitband.h
#define ALIAS4 0x42000000 #define BASE4 0x40000000 #define BIT_BAND4(ADDR_PAR, BIT_PAR) *((volatile unsigned *)(ALIAS4 + ((((ADDR_PAR - BASE4) << 3) + BIT_PAR) << 2)))
periphs.c
Power up, select the clock divider and select the pins for the peripherals you need; before the PLL is enabled.
periphs.c
#define PCONP (*((volatile unsigned *) 0x400FC0C4)) #define PCLKSEL0 (*((volatile unsigned *) 0x400FC1A8)) #define PCLKSEL1 (*((volatile unsigned *) 0x400FC1AC)) #define PINSEL0 (*((volatile unsigned *) 0x4002C000)) #define PINSEL1 (*((volatile unsigned *) 0x4002C004)) #define PINSEL2 (*((volatile unsigned *) 0x4002C008)) #define PINSEL3 (*((volatile unsigned *) 0x4002C00C)) void PeriphsInit (void) { //Peripheral power - Table 46 PCONP = 0; PCONP |= 1 << 1; //TIMER0 PCONP |= 1 << 3; //UART0 PCONP |= 1 << 4; //UART1 PCONP |= 1 << 9; //RTC PCONP |= 1 << 10; //SSP1 PCONP |= 1 << 15; //GPIO PCONP |= 1 << 30; //ENET //Peripheral clocks; default is 00 to divide by 4; specify 01 to divide by 1 PCLKSEL0 = 0; PCLKSEL0 |= 1 << 2; //TIM0 PCLKSEL0 |= 1 << 6; //UART0 PCLKSEL0 |= 1 << 8; //UART1 PCLKSEL0 |= 1 << 20; //SSP1 //Pin functions table 80. PINSEL0 = 0; PINSEL0 |= 1U << 4; //P0.02 01 TXD0 UART0 PINSEL0 |= 1U << 6; //P0.03 01 RXD0 UART0 PINSEL0 |= 2U << 14; //P0.07 10 SCK1 SSP1 PINSEL0 |= 2U << 16; //P0.08 10 MISO1 SSP1 PINSEL0 |= 2U << 18; //P0.09 10 MOSI1 SSP1 PINSEL0 |= 1U << 30; //P0.15 01 TXD1 UART1 PINSEL1 = 0; PINSEL1 |= 1U << 0; //P0.16 01 RXD1 UART1 PINSEL2 = 0; PINSEL2 |= 1U << 0; //P1.00 01 ENET_TXD0 PINSEL2 |= 1U << 2; //P1.01 01 ENET_TXD1 PINSEL2 |= 1U << 8; //P1.04 01 ENET_TX_EN PINSEL2 |= 1U << 16; //P1.08 01 ENET_CRS PINSEL2 |= 1U << 18; //P1.09 01 ENET_RXD0 PINSEL2 |= 1U << 20; //P1.10 01 ENET_RXD1 PINSEL2 |= 1U << 28; //P1.14 01 ENET_RX_ER PINSEL2 |= 1U << 30; //P1.15 01 ENET_REF_CLK PINSEL3 = 0; PINSEL3 |= 1U << 0; //P1.16 01 ENET_MDC PINSEL3 |= 1U << 2; //P1.17 01 ENET_MDIO }
system.c
Sets up the flash wait states, the main oscillator and finally starts the PLL to move from 12MHz to 96MHz. The peripheral clocks have to be set before the PLL is enabled.
system.c
#include "bitband.h" //Addresses #define FLASHCFG_ADDR 0x400FC000 // Flash Accelerator Configuration Register; controls flash access timing R/W 0x303A #define CCLKCFG_ADDR 0x400FC104 // CPU Clock Configuration Register R/W 0 #define CLKSRCSEL_ADDR 0x400FC10C // Clock Source Select Register R/W 0 #define SCS_ADDR 0x400FC1A0 // System Control and Status R/W 0 #define PLL0CON_ADDR 0x400FC080 // PLL0 Control Register R/W 0 #define PLL0CFG_ADDR 0x400FC084 // PLL0 Configuration Register R/W 0 #define PLL0STAT_ADDR 0x400FC088 // PLL0 Status Register RO 0 #define PLL0FEED_ADDR 0x400FC08C // PLL0 Feed Register WO NA #define USBCLKCFG_ADDR 0x400FC108 // USB Clock Configuration Register R/W 0 #define CLKOUTCFG_ADDR 0x400FC1C8 // Clock Output Configuration Register R/W 0 //Registers #define FLASHCFG *((volatile unsigned *) FLASHCFG_ADDR) #define CCLKCFG *((volatile unsigned *) CCLKCFG_ADDR) #define CLKSRCSEL *((volatile unsigned *) CLKSRCSEL_ADDR) #define PLL0CFG *((volatile unsigned *) PLL0CFG_ADDR) #define PLL0FEED *((volatile unsigned *) PLL0FEED_ADDR) #define USBCLKCFG *((volatile unsigned *) USBCLKCFG_ADDR) #define CLKOUTCFG *((volatile unsigned *) CLKOUTCFG_ADDR) //Bits #define PLLE0 BIT_BAND4( PLL0CON_ADDR, 0) #define PLLC0 BIT_BAND4( PLL0CON_ADDR, 1) #define PLOCK0 BIT_BAND4(PLL0STAT_ADDR, 26) //Reflects the PLL0 Lock status. #define OSCRANGE BIT_BAND4( SCS_ADDR, 4) #define OSCEN BIT_BAND4( SCS_ADDR, 5) #define OSCSTAT BIT_BAND4( SCS_ADDR, 6) void SystemInit() { //Flash config FLASHCFG &= ~(0xF << 12); // b15:12 0b0100 Flash accesses use 5 CPU clocks. Use for up to 100 MHz CPU clock. FLASHCFG |= 0x4 << 12 ; //Enable the main oscillator and wait for it to be ready OSCRANGE = 0; //Main Oscillator Range Select: 0= 1 MHz to 20 MHz; 1= 15 MHz to 25 MHz OSCEN = 1; //Main Oscillator Enable while (!OSCSTAT) __nop(); //Wait for Main Oscillator to be ready // bit 7:0 CCLKSEL: Divide value for the CPU clock (CCLK) from the PLL0 output. CCLKCFG = 2; // 2 == divide by 3 //PLL0 Clock Source Select CLKSRCSEL = 1; //01 selects the main oscillator //PLLO Configuration PLL0CFG = 11; //MSEL0=11 == M=12 == multiply by 24; NSEL=0 == divide by 1 PLL0FEED = 0xAA; PLL0FEED = 0x55; //PLL0 Control PLLE0 = 1; // PLL0 Enable PLL0FEED = 0xAA; PLL0FEED = 0x55; while (!PLOCK0) __nop(); // Wait for PLL to be locked PLLC0 = 1; // PLL0 Connect PLL0FEED = 0xAA; PLL0FEED = 0x55; //USB Clock divider USBCLKCFG = 5; // 5 == divide by 6 //Clock Output CLKOUTCFG = 0; //No clock output }
gpio.h
gpio.h
#define FIO0DIR_ADDR 0x2009C000 #define FIO1DIR_ADDR 0x2009C020 #define FIO2DIR_ADDR 0x2009C040 #define FIO0PIN_ADDR 0x2009C014 #define FIO1PIN_ADDR 0x2009C034 #define FIO2PIN_ADDR 0x2009C054 #define FIO0SET_ADDR 0x2009C018 #define FIO1SET_ADDR 0x2009C038 #define FIO2SET_ADDR 0x2009C058 #define FIO0CLR_ADDR 0x2009C01C #define FIO1CLR_ADDR 0x2009C03C #define FIO2CLR_ADDR 0x2009C05C #define FIO0SET(BIT_PAR) *((volatile unsigned *) FIO0SET_ADDR) = 1U << BIT_PAR #define FIO1SET(BIT_PAR) *((volatile unsigned *) FIO1SET_ADDR) = 1U << BIT_PAR #define FIO2SET(BIT_PAR) *((volatile unsigned *) FIO2SET_ADDR) = 1U << BIT_PAR #define FIO0CLR(BIT_PAR) *((volatile unsigned *) FIO0CLR_ADDR) = 1U << BIT_PAR #define FIO1CLR(BIT_PAR) *((volatile unsigned *) FIO1CLR_ADDR) = 1U << BIT_PAR #define FIO2CLR(BIT_PAR) *((volatile unsigned *) FIO2CLR_ADDR) = 1U << BIT_PAR #define ALIAS2 0x22000000 #define BASE2 0x20000000 #define BIT_BAND2(ADDR_PAR, BIT_PAR) *((volatile unsigned *)(ALIAS2 + ((((ADDR_PAR - BASE2) << 3) + BIT_PAR) << 2))) #define FIO0PIN(BIT_PAR) BIT_BAND2(FIO0PIN_ADDR, BIT_PAR) #define FIO1PIN(BIT_PAR) BIT_BAND2(FIO1PIN_ADDR, BIT_PAR) #define FIO2PIN(BIT_PAR) BIT_BAND2(FIO2PIN_ADDR, BIT_PAR) #define FIO0DIR(BIT_PAR) BIT_BAND2(FIO0DIR_ADDR, BIT_PAR) #define FIO1DIR(BIT_PAR) BIT_BAND2(FIO1DIR_ADDR, BIT_PAR) #define FIO2DIR(BIT_PAR) BIT_BAND2(FIO2DIR_ADDR, BIT_PAR)
led.c
led.c
#include <stdbool.h> #include "bitband.h" #include "gpio.h" #define LED1BIT 18 #define LED2BIT 20 #define LED3BIT 21 #define LED4BIT 23 #define LED1DIR BIT_BAND2(FIO1DIR_ADDR, LED1BIT) #define LED2DIR BIT_BAND2(FIO1DIR_ADDR, LED2BIT) #define LED3DIR BIT_BAND2(FIO1DIR_ADDR, LED3BIT) #define LED4DIR BIT_BAND2(FIO1DIR_ADDR, LED4BIT) #define LED1PIN BIT_BAND2(FIO1PIN_ADDR, LED1BIT) #define LED2PIN BIT_BAND2(FIO1PIN_ADDR, LED2BIT) #define LED3PIN BIT_BAND2(FIO1PIN_ADDR, LED3BIT) #define LED4PIN BIT_BAND2(FIO1PIN_ADDR, LED4BIT) #define LED1SET FIO1SET = 1U << LED1BIT #define LED1CLR FIO1CLR = 1U << LED1BIT #define LED2SET FIO1SET = 1U << LED2BIT #define LED2CLR FIO1CLR = 1U << LED2BIT #define LED3SET FIO1SET = 1U << LED3BIT #define LED3CLR FIO1CLR = 1U << LED3BIT #define LED4SET FIO1SET = 1U << LED4BIT #define LED4CLR FIO1CLR = 1U << LED4BIT void LedInit() { LED1DIR = 1; LED2DIR = 1; LED3DIR = 1; LED4DIR = 1; } void Led1Set(bool value) { if (value) LED1SET; else LED1CLR; } void Led2Set(bool value) { if (value) LED2SET; else LED2CLR; } void Led3Set(bool value) { if (value) LED3SET; else LED3CLR; } void Led4Set(bool value) { if (value) LED4SET; else LED4CLR; } void Led1Tgl() { if (LED1PIN) LED1CLR; else LED1SET; } void Led2Tgl() { if (LED2PIN) LED2CLR; else LED2SET; } void Led3Tgl() { if (LED3PIN) LED3CLR; else LED3SET; } void Led4Tgl() { if (LED4PIN) LED4CLR; else LED4SET; } bool Led1Get() { return LED1PIN; } bool Led2Get() { return LED2PIN; } bool Led3Get() { return LED3PIN; } bool Led4Get() { return LED4PIN; }
handlers.c
Contains those handlers which are not defined elsewhere in code. Any handler needs to be defined with the __irq
attribute.
The hard fault handler is configured to just flash led 4; this leaves the other leds available to help locate the source of the hard fault: typically something like an array overflow or accessing a peripheral that has not been powered up. Faults are saved in the fault module for later debugging
handlers.c
#include <stdint.h> #include "fault.h" #include "led.h" __irq void DefaultHandler() { FaultSave(FAULT_TYPE_DEFAULT); int value = 0; int count = 0; while (1) { count++; if (count > 10000000) { value = !value; Led1Set( value); Led2Set(!value); Led3Set(!value); Led4Set( value); count = 0; } } } __irq void HardFaultHandler() { FaultSave(FAULT_TYPE_HARD); int value = 0; int count = 0; while (1) { count++; if (count > 10000000) { value = !value; Led4Set(value); count = 0; } } }
main.c
Calls PeriphsInit
to power up and select the peripheral clocks, then SystemInit
and LedInit
. After that you can initialise anything else then go into an infinite loop as this routine never exits.
main.c
#include <stdint.h> #include <stdbool.h> #include "periphs.h" #include "system.h" #include "led.h" int main() { PeriphsInit(); SystemInit(); LedInit(); int count = 0; while (true) { count++; if (count > 10000000) { Led1Set(!Led1Get()); count = 0; } } }
Revision 71:2f8af23950de, committed 2022-06-03
- Comitter:
- andrewboyson
- Date:
- Fri Jun 03 11:51:13 2022 +0000
- Parent:
- 70:3ae450c74c5e
- Commit message:
- Added can module
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/can/can.c Fri Jun 03 11:51:13 2022 +0000 @@ -0,0 +1,64 @@ + +#include "log.h" +#include "mstimer.h" + +#define AFMR *((volatile unsigned *)0x4003C000) // Acceptance Filter Mode Register + +#define CAN2MOD *((volatile unsigned *)0x40048000) // CAN Mode register +#define CAN2CMR *((volatile unsigned *)0x40048004) // CAN Command register +#define CAN2GSR *((volatile unsigned *)0x40048008) // CAN Global Status register +#define CAN2ICR *((volatile unsigned *)0x4004800C) // CAN Interrupt and Capture Register +#define CAN2IER *((volatile unsigned *)0x40048010) // CAN Interrupt Enable Register +#define CAN2BTR *((volatile unsigned *)0x40048014) // CAN Bus Timing Register +#define CAN2TFI1 *((volatile unsigned *)0x40048030) // CAN Transmit Frame Information register +#define CAN2TID1 *((volatile unsigned *)0x40048034) // CAN Transmit Identifier Register +#define CAN2TDA1 *((volatile unsigned *)0x40048038) // CAN Transmit Data Register A +#define CAN2TDB1 *((volatile unsigned *)0x4004803C) // CAN Transmit Data Register B +#define CAN2RFS *((volatile unsigned *)0x40048020) // CAN Receive Frame Status register +#define CAN2RID *((volatile unsigned *)0x40048024) // CAN Receive Identifier register +#define CAN2RDA *((volatile unsigned *)0x40048028) // CAN Receive Data register A +#define CAN2RDB *((volatile unsigned *)0x4004802C) // CAN Receive Data register B + +void (*CanReceive)(uint16_t id, int length, uint32_t dataA, uint32_t dataB); +void CanInit() +{ + LogTime("Can init started\r\n"); + /* + 00: BRP = 95 : Clock is 96 / 4 = 24MHz and we want 1.000MHz so prescale by BRP+1 = 24: BRP = 23. + 14: SJW = 3 : 4 can clocks + 16: TESG1 = 4 : 5 can clocks + 20: TESG2 = 3 : 4 can clocks + */ + CAN2BTR = 0; + CAN2BTR |= 23 << 00; + CAN2BTR |= 3 << 14; + CAN2BTR |= 4 << 16; + CAN2BTR |= 3 << 20; + + AFMR |= 1 << 1; //Accept all messages + + CAN2MOD = 0; //Controller to operating mode +} +void CanSend(uint16_t id, int length, uint32_t dataA, uint32_t dataB) +{ + if (length > 8) length = 8; + CAN2CMR |= 1 << 5; //STB1 Select Tx Buffer 1 + CAN2TFI1 = 0; + CAN2TFI1 |= length << 16; //DLC Data Length Code + CAN2TFI1 |= 0 << 30; //RTR Remote TRansmission + CAN2TFI1 |= 0 << 31; // FF Extended frame (0 = 11 bit id; 1 = 29 bit id) + CAN2TID1 = id; + CAN2TDA1 = dataA; + CAN2TDB1 = dataB; + CAN2CMR |= 1 << 0; //TR Transmission Request +} +void CanMain() +{ + if (CAN2GSR & 0x01) //RBS Receive Buffer Status - At least one complete message is available in CANxRFS CANxRID CANxRDA CANxRDB + { + uint16_t id = CAN2RID & 0x3FF; + int length = (CAN2RFS >> 16) & 0xF; + CanReceive(id, length, CAN2RDA, CAN2RDB); + CAN2CMR |= 1 << 2; //RRB Release Receive Buffer + } +} \ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/can/can.h Fri Jun 03 11:51:13 2022 +0000 @@ -0,0 +1,5 @@ +#include <stdint.h> +extern void (*CanReceive)(uint16_t id, int length, uint32_t dataA, uint32_t dataB); +extern void CanSend (uint16_t id, int length, uint32_t dataA, uint32_t dataB); +extern void CanInit(void); +extern void CanMain(void); \ No newline at end of file
--- a/i2c/i2c1.c Tue May 18 16:25:19 2021 +0000 +++ b/i2c/i2c1.c Fri Jun 03 11:51:13 2022 +0000 @@ -59,7 +59,7 @@ if (I2C1Busy && MsTimerRelative(_msTimeOut, TIMEOUT_MS)) { - LogTime("I2C1 -> Timeout\r\n"); + if (I2C1Trace) LogTime("I2C1 -> Timeout\r\n"); *_pResult = I2C1_RESULT_TIMED_OUT; I2C1Busy = false; I2C1CONSET = 0x10; //Set STO bit @@ -74,19 +74,19 @@ { case 0x08: //Received START case 0x10: //Received a repeated START - if (I2C1Trace) { LogTimeF("I2C1 -> addr %02x + W\r\n", _addr); } + if (I2C1Trace) LogTimeF("I2C1 -> addr %02x + W\r\n", _addr); I2C1DAT = (_addr << 1) | 0; //Send the address + W I2C1CONCLR = 0x08; //Clear S1 index = 0; break; case 0x18: //received ACK after address - if (I2C1Trace) { LogTimeF("I2C1 -> data%d %02x\r\n", index, _pData[index]); } + if (I2C1Trace) LogTimeF("I2C1 -> data%d %02x\r\n", index, _pData[index]); I2C1DAT = _pData[index]; //Load the data to be sent I2C1CONCLR = 0x20; //Reset the start bit I2C1CONCLR = 0x08; //Clear S1 break; case 0x20: //received NAK after address - if (I2C1Trace) { LogTime("I2C1 -> Stop\r\n"); } + if (I2C1Trace) LogTime("I2C1 -> Stop\r\n"); *_pResult = I2C1_RESULT_FAILED; I2C1Busy = false; I2C1CONSET = 0x10; //Set STO bit @@ -96,27 +96,27 @@ index++; if (index >= _length) { - if (I2C1Trace) { LogTime("I2C1 -> Stop\r\n"); } + if (I2C1Trace) LogTime("I2C1 -> Stop\r\n"); *_pResult = I2C1_RESULT_OK; I2C1Busy = false; I2C1CONSET = 0x10; //Set STO bit } else { - if (I2C1Trace) { LogTimeF("I2C1 -> data%d %02x\r\n", index, _pData[index]); } + if (I2C1Trace) LogTimeF("I2C1 -> data%d %02x\r\n", index, _pData[index]); I2C1DAT = _pData[index];//Load the data to be sent } I2C1CONCLR = 0x08; //Clear S1 break; case 0x30: //received NAK after data - if (I2C1Trace) { LogTime("I2C1 -> Stop\r\n"); } + if (I2C1Trace) LogTime("I2C1 -> Stop\r\n"); *_pResult = I2C1_RESULT_FAILED; I2C1Busy = false; I2C1CONSET = 0x10; //Set STO bit I2C1CONCLR = 0x08; //Clear S1 break; case 0x38: //Arbitration lost - if (I2C1Trace) { LogTime("I2C1 -> Start\r\n"); } + if (I2C1Trace) LogTime("I2C1 -> Start\r\n"); *_pResult = I2C1_RESULT_FAILED; I2C1Busy = false; I2C1CONSET = 0x20; //Set STA bit