int can_frequency(can_t *obj, int f) {
int pclk = PeripheralClock;
int btr = can_speed(pclk, (unsigned int)f, 1);
if (btr > 0) {
uint32_t modmask = can_disable(obj);
obj->dev->BTR = btr;
obj->dev->MOD = modmask;
return 1;
} else {
return 0;
}
}
/**
* @brief Configures the desired CAN device with the desired frequency.
*
* @param obj The can device to configure.
* @param f The desired frequency.
*
* @return RTEMS_SUCCESSFUL if could be set, RTEMS_INVALID_NUMBER otherwise.
*/
static rtems_status_code can_frequency(
const can_driver_entry *const obj,
const can_freq freq
)
{
rtems_status_code sc = RTEMS_INVALID_NUMBER;
const uint32_t btr = can_speed( LPC176X_CCLK, LPC176X_PCLKDIV, freq, 1 );
if ( btr != WRONG_BTR_VALUE ) {
sc = RTEMS_SUCCESSFUL;
uint32_t modmask = can_disable( obj );
obj->device->BTR = btr;
obj->device->MOD = modmask;
} /*else couldnt found a good timing for the desired frequency,
return RTEMS_INVALID_NUMBER.*/
return sc;
}
int can_frequency(can_t *obj, int f)
{
int pclk = HAL_RCC_GetPCLK1Freq();
int btr = can_speed(pclk, (unsigned int)f, 1);
CAN_TypeDef *can = (CAN_TypeDef *)(obj->can);
if (btr > 0) {
can->MCR |= CAN_MCR_INRQ ;
while((can->MSR & CAN_MSR_INAK) != CAN_MSR_INAK) {
}
can->BTR = btr;
can->MCR &= ~(uint32_t)CAN_MCR_INRQ;
while((can->MSR & CAN_MSR_INAK) == CAN_MSR_INAK) {
}
return 1;
} else {
return 0;
}
}
int can_frequency(can_t *obj, int f)
{
int pclk = HAL_RCC_GetPCLK1Freq();
int btr = can_speed(pclk, (unsigned int)f, 1);
CAN_TypeDef *can = obj->CanHandle.Instance;
uint32_t tickstart = 0;
int status = 1;
if (btr > 0) {
can->MCR |= CAN_MCR_INRQ ;
/* Get tick */
tickstart = HAL_GetTick();
while ((can->MSR & CAN_MSR_INAK) != CAN_MSR_INAK) {
if ((HAL_GetTick() - tickstart) > 2) {
status = 0;
break;
}
}
if (status != 0) {
/* Do not erase all BTR registers (e.g. silent mode), only the
* ones calculated in can_speed */
can->BTR &= ~(CAN_BTR_TS2 | CAN_BTR_TS1 | CAN_BTR_SJW | CAN_BTR_BRP);
can->BTR |= btr;
can->MCR &= ~(uint32_t)CAN_MCR_INRQ;
/* Get tick */
tickstart = HAL_GetTick();
while ((can->MSR & CAN_MSR_INAK) == CAN_MSR_INAK) {
if ((HAL_GetTick() - tickstart) > 2) {
status = 0;
break;
}
}
if (status == 0) {
error("can ESR 0x%04x.%04x + timeout status %d", (can->ESR & 0xFFFF0000) >> 16, (can->ESR & 0xFFFF), status);
}
int main()
{
uint8_t do_lpm, is_ext;
int i, j, k;
uint32_t msgid;
WDTCTL = WDTPW | WDTHOLD;
DCOCTL = CALDCO_16MHZ;
BCSCTL1 = CALBC1_16MHZ;
BCSCTL2 = DIVS_1;
BCSCTL3 = LFXT1S_2;
while (BCSCTL3 & LFXT1OF)
;
P1SEL &= ~BIT0;
P1SEL2 &= ~BIT0;
P1DIR |= BIT0;
P1OUT &= ~BIT0;
sleep_counter = SLEEP_COUNTER;
inbuf[8] = '\0';
can_init();
if (can_speed(500000, 1, 3) < 0) {
P1OUT |= BIT0;
LPM4;
}
// LCD init
P2SEL &= ~(BIT0 | BIT5);
P2SEL2 &= ~(BIT0 | BIT5);
P2DIR |= BIT0 | BIT5;
P2OUT |= BIT0 | BIT5;
msp1202_init();
msp1202_puts("CAN printer\n0x00000080-\n");
can_rx_setmask(0, 0xFFFFFFFF, 1);
can_rx_setmask(1, 0xFFFFFFFF, 1);
can_rx_setfilter(0, 0, 0x00000080);
can_rx_mode(0, MCP2515_RXB0CTRL_MODE_RECV_STD_OR_EXT);
can_ioctl(MCP2515_OPTION_LOOPBACK, 0);
can_ioctl(MCP2515_OPTION_ONESHOT, 0);
can_ioctl(MCP2515_OPTION_ROLLOVER, 1);
/* Flowchart for program flow:
*
* START
* |
* +---------<-------------------+-----------<-----------------------+
* | | |
* \|/ /|\ |
* -------------- | |
* / \ +------+ | |
* < Is IRQ pending? > No->---| LPM4 |->--+ |
* \ / +------+ /|\
* ------------- |
* Yes |
* | |
* \_/ |
* ----------- ------------- |
* / \ / \ |
* < Is IRQ_ERROR? > Yes->--< Is IRQ_HANDLED? > Yes->-------------------------+
* \ / \ / |
* ----------- ------------- |
* No No |
* | | /|\
* \_/ \_/ |
* -------- -------- +-----------------+ |
* / \ / \ | Cancel TX using | |
* < Is IRQ_RX? > No->---->---< Is IRQ_TX? > Yes->--| can_tx_cancel() |->----+
* \ / \ / +-----------------+ |
* -------- -------- |
* Yes No |
* | | /|\
* \_/ \_/ |
* +----------------+ +-------------------+ |
* | Pull data | | Bus error, wait | |
* | using can_recv | | 100ms and recheck |->---------------------------+
* +----------------+ | IRQ. | |
* | +-------------------+ |
* \_/ |
* +--------------+ /|\
* | Write buffer | |
* | contents to | |
* | LCD using |->--------------------------->---------------------------+
* | msp1202_puts |
* +--------------+
*
*
*
*/
while(1) {
do_lpm = 1;
if (mcp2515_irq) {
irq = can_irq_handler();
if (irq & MCP2515_IRQ_ERROR) {
if ( !(irq & MCP2515_IRQ_HANDLED) ) {
if (irq & MCP2515_IRQ_TX) {
can_tx_cancel();
} else {
// Bus error; wait 100ms, recheck
P1OUT |= BIT0;
__delay_cycles(1600000);
P1OUT &= ~BIT0;
do_lpm = 0;
}
} else {
// RX overflow, most likely
msp1202_puts("RX OVERFLOW\n");
}
}
if (irq & MCP2515_IRQ_RX) {
j = 0;
k = can_rx_pending();
do {
i = can_recv(&msgid, &is_ext, inbuf+j);
if ( !(i & 0x40) ) {
j += i;
}
//msp1202_putc(k + '0', 0); msp1202_putc(' ', 0);
} while ( (k = can_rx_pending()) >= 0 );
//inbuf[j++] = '\n'; inbuf[j] = '\0';
inbuf[j] = '\0';
msp1202_puts((char*)inbuf);
//msp1202_putc('\n', 1);
} else {
if (irq & MCP2515_IRQ_TX) {
can_tx_cancel();
}
}
}
if ( do_lpm && !(mcp2515_irq & MCP2515_IRQ_FLAGGED) ) {
LPM4;
}
}
return 0;
}
