Other Parts Discussed in Thread: HALCOGEN
Hi,
I have a problem using multi-buffered mode on SCI-A/lin.
Basically, I want to generate an interrupt every n bytes in order to not overload the cpu too much.
I thought that with multi-buffered mode I can choose after how many bytes generate an interrupt RXDY but it seems not working.
Here is my code:
void sciInit(void)
{
/** - bring SCI1 out of reset */
sci->GCR0 = 0U;
sci->GCR0 = 1U;
/** - Disable all interrupts */
sci->CLEARINT = 0xFFFFFFFFU;
sci->CLEARINTLVL = 0xFFFFFFFFU;
/** - global control 1 */
sci->GCR1 = (uint32)((uint32)1U << 25U) /* enable transmit */
| (uint32)((uint32)1U << 24U) /* enable receive */
| (uint32)((uint32)1U << 5U) /* internal clock (device has no clock pin) */
| (uint32)((uint32)(1U-1U) << 4U) /* number of stop bits */
| (uint32)((uint32)0U << 3U) /* even parity, otherwise odd */
| (uint32)((uint32)0U << 2U) /* enable parity */
| (uint32)((uint32)1U << 1U) /* asynchronous timing mode */
| (uint32)((uint32)1U << 16U) /* LOOP BACK MODE enabled for test*/
| (uint32)((uint32)1U << 10U); /* multi buffered mode enabled */
/** - set baudrate */
sci->BRS = 650U; /* baudrate */
/** - transmission length */
sci->FORMAT = /*0x0700 |*/ (8U - 1U); /* length (8 characters of size 8, according to datasheet) */
/** - set SCI1 pins functional mode */
sci->PIO0 = (uint32)((uint32)1U << 2U) /* tx pin */
| (uint32)((uint32)1U << 1U); /* rx pin */
/** - set SCI1 pins default output value */
sci->PIO3 = (uint32)((uint32)0U << 2U) /* tx pin */
| (uint32)((uint32)0U << 1U); /* rx pin */
/** - set SCI1 pins output direction */
sci->PIO1 = (uint32)((uint32)0U << 2U) /* tx pin */
| (uint32)((uint32)0U << 1U); /* rx pin */
/** - set SCI1 pins open drain enable */
sci->PIO6 = (uint32)((uint32)0U << 2U) /* tx pin */
| (uint32)((uint32)0U << 1U); /* rx pin */
/** - set SCI1 pins pullup/pulldown enable */
sci->PIO7 = (uint32)((uint32)0U << 2U) /* tx pin */
| (uint32)((uint32)0U << 1U); /* rx pin */
/** - set SCI1 pins pullup/pulldown select */
sci->PIO8 = (uint32)((uint32)1U << 2U) /* tx pin */
| (uint32)((uint32)1U << 1U); /* rx pin */
/** - set interrupt level */
sci->SETINTLVL = (uint32)((uint32)0U << 26U) /* Framing error */
| (uint32)((uint32)0U << 25U) /* Overrun error */
| (uint32)((uint32)0U << 24U) /* Parity error */
| (uint32)((uint32)0U << 9U) /* Receive */
| (uint32)((uint32)0U << 8U) /* Transmit */
| (uint32)((uint32)0U << 1U) /* Wakeup */
| (uint32)((uint32)0U << 0U); /* Break detect */
/** - set interrupt enable */
sci->SETINT = (uint32)((uint32)0U << 26U) /* Framing error */
| (uint32)((uint32)0U << 25U) /* Overrun error */
| (uint32)((uint32)0U << 24U) /* Parity error */
| (uint32)((uint32)1U << 9U) /* Receive interrupt*/
| (uint32)((uint32)0U << 1U) /* Wakeup */
| (uint32)((uint32)0U << 0U); /* Break detect */
/** - Finaly start SCI1 */
sci->GCR1 |= 0x80U;
}
To test the peripheral I just send a bunch of dummy bytes and check if ISR is executed (since I'm working in loopback).
Without multi-buffer I can have an interrupt every byte sent and it's working fine, so the interrupts are well configurated but with multi-buffered mode ISR is never executed (I though ISR was executed every 8 bytes trasmitted).
Is it possible to generate an interrupt after n bytes without using DMA? If yes, how to get data? SCIRD register is only 1byte-length and I'm not understanding where the data will be available.
Thanks,
Marco.
