uart1: fixes, UART1_RX_FLAG_SEND

- major fixes all over
- directly send the received string/data via `printf()`
  even without providing a buffer
  uart1_receive(s=0, 120, UART1_RX_FLAG_SEND)

gpio.h

@@ -23,7 +23,7 @@
  * 0.15: (45) AD1.5 Ineg (EINT)
  * 0.16: (46) SSP SSEL/MCLK MAT0.2
  * 0.17: (47) SSP SCK
- * 0.18: (53) SSP MISO
+ * 0.18: (53) SSP MISO (CAP1.3)
  * 0.19: (54) SSP MOSI
  * 0.20: (55) SSL SSEL ADC
  * 0.21: (1) AD1.6 Vpos (PWM)
@@ -33,9 +33,9 @@
  * 0.25: (9) AOUT (AD0.4)
  * 0.26:
  * 0.27:
- * 0.28: (13) AD0.1 (MAT)
- * 0.29: (14) AD0.2 (MAT)
- * 0.30: (15) AD0.3 (MAT, EINT)
+ * 0.28: (13) AD0.1 (MAT0.2, CAP0.2)
+ * 0.29: (14) AD0.2 (MAT0.3, CAP0.3)
+ * 0.30: (15) AD0.3 (CAP0.0, EINT3)
  * 0.31: (17) USB UP_LED
  *
  * 1.16: (16) GPIO OUT (internal pull-up)

uart.h

@@ -48,10 +48,12 @@ inline static void streol(char *s, int n)
 }
 
 enum {
-	UART1_RX_FLAG_READLINE = 1,
+	UART1_RX_FLAG_READLINE       = 1,
 	UART1_RX_FLAG_ALL_OR_NOTHING = 2,
-	UART1_RX_FLAG_FLUSH = 4,
+	UART1_RX_FLAG_FLUSH          = 4,
+	UART1_RX_FLAG_SEND           = 8
 };
+
 unsigned int uart1_receive(char *s, unsigned int n, unsigned int flags);
 int uart1_send(const char *s, unsigned int n);
 

uart1.c

@@ -5,17 +5,20 @@
 #include <lpc2148/vic.h>
 #include <string.h>
 #include "mainloop.h"
+#include "message.h"
+#include "parser.h"
 
 static char uart1_buffer[128];
 #define buffer_size (sizeof(uart1_buffer))
-#define buffer(p) uart1_buffer[(p) & (buffer_size - 1)]
+#define buffer_mask (buffer_size-1)
+#define buffer(p) uart1_buffer[(p) & buffer_mask]
 
 // all access must be with irqs disabled, no volatile
 
-unsigned int tx_read;
-unsigned int tx_write;
-unsigned int rx_read;
-unsigned int rx_write;
+static unsigned int tx_read;
+static unsigned int tx_write;
+static unsigned int rx_read;
+static unsigned int rx_write;
 
 // uart1_buffer invariants:
 // buffer_size = 2^n
@@ -28,20 +31,21 @@ unsigned int rx_write;
 inline static
 void free_rx_space()
 {
+	if (rx_read + buffer_size == tx_write)
+		return;
 	if (rx_read == rx_write) {
-		rx_read = rx_write = tx_read - buffer_size;
+		rx_read = rx_write = tx_write - buffer_size;
 		return;
 	}
 	if (tx_read == tx_write) {
 		tx_read = tx_write = rx_read + buffer_size;
 		return;
 	}
-	if (rx_read == tx_write)
-		return;
 	unsigned int nrx_write = tx_write - buffer_size;
-	rx_read  = nrx_write;
+	unsigned int nrx_read = nrx_write;
 	while (rx_read != rx_write)
 		buffer(nrx_write++) = buffer(rx_read++);
+	rx_read  = nrx_read;
 	rx_write = nrx_write;
 }
 
@@ -109,6 +113,29 @@ int uart1_status()
 unsigned int uart1_interrupt_count;
 unsigned int uart1_overflow;
 unsigned int uart1_frame_errors;
+unsigned int uart1_mode;
+
+struct uart1_match {
+	unsigned char size; // available message length
+	unsigned char val;  // eol char
+	unsigned char max;  // max line length to wait for
+	unsigned char mask; // mask char for eol
+} uart1_match = {
+	.size = 0,
+	.max  = 96,
+	.mask = 0xff,
+	.val  = '\n',
+};
+
+const struct keywords uart1_variable_names[] = {
+	VARIABLE("uart_mode",     &uart1_mode),
+	VARIABLE("uart_match",    &uart1_match),
+	VARIABLE("uart_irqs",     &uart1_interrupt_count),
+	VARIABLE("uart_overflow", &uart1_overflow),
+	VARIABLE("uart_errors",   &uart1_frame_errors),
+	VARIABLE("uart_buffer",   &uart1_buffer),
+	KW_END
+};
 
 inline static
 unsigned int drain_rx_fifo(unsigned int lsr)
@@ -127,10 +154,16 @@ unsigned int drain_rx_fifo(unsigned int lsr)
 				break;
 			}
 		}
-		buffer(rx_write++) = U1RBR;
+		char d = U1RBR;
+		buffer(rx_write++) = d;
 		iir = U1IIR;
 		lsr = U1LSR;
+		unsigned int n = rx_write - rx_read;
+		if ((d & uart1_match.mask) == uart1_match.val
+		    || n >= uart1_match.max)
+			uart1_match.size = n;
 	}
+
 	if (!(lsr & UART_LSR_RDR))
 		U1IER |= UART_IER_RBR;
 	return lsr;
@@ -164,7 +197,8 @@ void uart1_init()
 	U1LCR = 0;
 	U1IER = 0;
 	barrier();
-	tx_read = tx_write = rx_read = rx_write = 0;
+	rx_read = rx_write = 0;
+	tx_read = tx_write = buffer_size;
 	
 	U1FCR = UART_FCR_Enable | UART_FCR_RxReset | UART_FCR_TxReset | UART_FCR_RxTrigger_14;
 	U1LCR = UART_LCR_DLAB;
@@ -177,6 +211,7 @@ void uart1_init()
 
 	baudrate1 = baud_rates[baud1_select].baud;
 
+	U1IER |= UART_IER_RBR;
 	VICVectAddrs[IrqVec_UART1] = uart1_isr;
 	VICVectCntl[IrqVec_UART1] = VICVectCntl_UART1;
 	VICIntEnable = VIC_UART1;
@@ -185,11 +220,19 @@ void uart1_init()
 int uart1_send(const char *s, unsigned int n)
 {
 	unsigned int iflag = disable_irq(IRQ_DISABLE);
-	if (free_tx_space(n) < n)
-		return 0;
-	unsigned int tx_write = tx_write;
-	memcpy(&buffer(tx_write), s , n);
+	if (free_tx_space(n) < n) {
+		n = 0;
+		goto full;
+	}
+	unsigned int nn = buffer_size - (tx_write & buffer_mask);
+	if (nn >= n)
+		memcpy(&buffer(tx_write), s, n);
+	else {
+		memcpy(&buffer(tx_write), s, nn);
+		memcpy(&buffer(0), s+nn, n - nn);
+	}
 	tx_write += n;
+full:
 	uart1_poll(U1LSR);
 	enable_irq(iflag);
 	return n;
@@ -199,31 +242,87 @@ unsigned int uart1_receive(char *s, unsigned int n, unsigned int flags)
 {
 	unsigned int iflag = disable_irq(IRQ_DISABLE);
 	drain_rx_fifo(U1LSR);
+	unsigned int b = rx_write - rx_read;
+	enable_irq(iflag);
+
 	unsigned int r = 0;
-	if (rx_write - rx_read < n && flags & UART1_RX_FLAG_ALL_OR_NOTHING)
-		goto empty;
 	if (!n)
 		goto flush;
+
+	if (b > n)
+		b = n;
 	if (flags & UART1_RX_FLAG_READLINE) {
+		if (b >= n)
+			b = n - 1;
 		unsigned int i;
-		for (i = rx_read; i < rx_write; i++)
-			if (buffer(i) == '\n')
+		for (i = 0; i < b; i++)
+			if ((buffer(rx_read+i) & uart1_match.mask) == uart1_match.val)
 				break;
-		i -= rx_read;
-		i++;
-		if (i >= n)
-			i = n - 1;
-		n = i;
-		s[n] = '\0';
+		if (i == b && i < uart1_match.max && n > uart1_match.max)
+			b = 0;
+		else
+			b = i;
+		if (s)
+			s[b] = '\0';
 	}
-	unsigned int b = rx_write - rx_read;
-	if (n)
-		memcpy(s, &buffer(rx_read), n);
-	rx_read += n;
+	else if (b < n && flags & UART1_RX_FLAG_ALL_OR_NOTHING)
+		goto empty;
+
+	if (!b)
+		goto empty;
+
+	unsigned int bb = buffer_size - (rx_read & buffer_mask);
+	if (s)
+		if (bb >= b)
+			memcpy(s, &buffer(rx_read), b);
+		else {
+			memcpy(s, &buffer(rx_read), bb);
+			memcpy(s + bb, &buffer(0), b - bb);
+		}
+
+	if (flags & UART1_RX_FLAG_SEND)
+		if (flags & UART1_RX_FLAG_READLINE) {
+			if (s)
+				printf("UT %s←UT\n", s);
+			else if (bb >= b)
+				printf("UT %.*s←UT\n", b, &buffer(rx_read));
+			else
+				printf("UT %.*s%.*s←UT\n",
+				       bb, &buffer(rx_read),
+				       b - bb, &buffer(rx_read + bb) );
+		}
+		else {
+			printf("UX");
+			for (unsigned int i=0; i < b; i++)
+				printf(" %02x", buffer(rx_read+i));
+			printf("\n");
+		}
+
+	rx_read += b;
+	r = b;
+
 flush:
-	if (flags & UART1_RX_FLAG_FLUSH)
+	if (flags & UART1_RX_FLAG_FLUSH) {
 		rx_read = rx_write;
+		uart1_match.size = 0;
+	}
+
 empty:
+	U1IER |= UART_IER_RBR;
+
+	iflag = disable_irq(IRQ_DISABLE);
+	b = rx_write - rx_read;
+	if (b >= uart1_match.max)
+		uart1_match.size = b;
+	else {
+		uart1_match.size = 0;
+		for (unsigned int i=0; i<b; i++)
+			if ((buffer(rx_read+i) & uart1_match.mask) == uart1_match.val) {
+				uart1_match.size = i;
+				break;
+			}
+	}
 	enable_irq(iflag);
+
 	return r;
 }