From: Michel Pollet <buserror@gmail.com>
Date: Tue, 15 Mar 2011 13:37:09 +0000 (+0000)
Subject: test: Updated uart_echo
X-Git-Tag: v1.0a8~8
X-Git-Url: https://git.htl-mechatronik.at/public/?a=commitdiff_plain;h=613903e9fc0d7c809650909a68fc519b1731537e;p=sx%2Fsimavr.git

test: Updated uart_echo

Now set a baud rate, to excersize the new logic in the uart
simulator.
Also added a VCD file

Signed-off-by: Michel Pollet <buserror@gmail.com>
---

diff --git a/tests/atmega88_uart_echo.c b/tests/atmega88_uart_echo.c
index b0ea04c..17be737 100644
--- a/tests/atmega88_uart_echo.c
+++ b/tests/atmega88_uart_echo.c
@@ -24,6 +24,18 @@ AVR_MCU(F_CPU, "atmega88");
 // tell simavr to listen to commands written in this (unused) register
 AVR_MCU_SIMAVR_COMMAND(&GPIOR0);
 
+/*
+ * This small section tells simavr to generate a VCD trace dump with changes to these
+ * registers.
+ * Opening it with gtkwave will show you the data being pumped out into the data register
+ * UDR0, and the UDRE0 bit being set, then cleared
+ */
+const struct avr_mmcu_vcd_trace_t _mytrace[]  _MMCU_ = {
+	{ AVR_MCU_VCD_SYMBOL("UDR0"), .what = (void*)&UDR0, },
+	{ AVR_MCU_VCD_SYMBOL("UDRE0"), .mask = (1 << UDRE0), .what = (void*)&UCSR0A, },
+	{ AVR_MCU_VCD_SYMBOL("GPIOR1"), .what = (void*)&GPIOR1, },
+};
+
 static int uart_putchar(char c, FILE *stream) {
 	if (c == '\r')
 		uart_putchar('\r', stream);
@@ -42,6 +54,7 @@ volatile uint8_t done = 0;
 ISR(USART_RX_vect)
 {
 	uint8_t b = UDR0;
+	GPIOR1 = b; // for the trace file
 	buffer[bindex++] = b;
 	buffer[bindex] = 0;
 	if (b == '\n')
@@ -55,9 +68,23 @@ int main()
 
 	stdout = &mystdout;
 
-	// enable receiver
+	UCSR0C |= (3 << UCSZ00); // 8 bits
+	// see http://www.nongnu.org/avr-libc/user-manual/group__util__setbaud.html
+#define BAUD 38400
+#include <util/setbaud.h>
+	UBRR0H = UBRRH_VALUE;
+	UBRR0L = UBRRL_VALUE;
+#if USE_2X
+	UCSR0A |= (1 << U2X0);
+#else
+	UCSR0A &= ~(1 << U2X0);
+#endif
+
+	// enable receiver & transmitter
 	UCSR0B |= (1 << RXCIE0) | (1 << RXEN0) | (1 << TXEN0);
 
+	// this tells simavr to start the trace
+	GPIOR0 = SIMAVR_CMD_VCD_START_TRACE;
 	sei();
 	printf("Hey there, this should be received back\n");