This is a thoughtful request. The (for dsPIC30/33 and PIC24 families) is now legacy (superseded by XC16), but many engineers still maintain projects on it.
// ------------------------------------------------------------ // 2. CIRCULAR BUFFER (with DMA/DSP-friendly alignment) // ------------------------------------------------------------ typedef struct volatile unsigned int head; volatile unsigned int tail; unsigned int mask; // size-1, must be power of two unsigned char Y_DATA_SPACE *buffer; // force Y-space for DSP unsigned int len; c30_cbuf_t;
A for C30 would address its most common real-world pain points: poor RAM banking management , lack of built-in circular buffer support for DSP , and verbose ISR syntax . mplab c30 compiler
// Initialize (buffer must be 2^N, ideally in Y data space) void c30_cbuf_init(c30_cbuf_t *cb, unsigned char *buf, unsigned int size) cb->head = 0; cb->tail = 0; cb->mask = size - 1; cb->buffer = buf; cb->len = size;
// Example: MAC with saturation inline int mac_saturate(int acc, int a, int b) acc += a * b; if (acc > 32767) acc = 32767; if (acc < -32768) acc = -32768; return acc; This is a thoughtful request
INTERRUPT(_U1RXInterrupt, 6) while (U1STAbits.URXDA) c30_cbuf_put(&uart_rx, U1RXREG);
cb->buffer[cb->head] = data; cb->head = next_head; return 0; volatile unsigned int tail
// ------------------------------------------------------------ // 3. ISR MACRO (fixes C30's verbose/error-prone vector syntax) // ------------------------------------------------------------ #define INTERRUPT(vector, priority) void ((interrupt, auto_psv)) _ ## vector (void)