From 23dc9a63ae8bc982d9352cfb7a3f508d8a08c374 Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Mon, 17 Dec 2012 22:58:49 -0800 Subject: [PATCH] altos: Make micropeak 'serial' interface work I prototyped the mpserial interface on a breadboard and tuned the circuit to register the LED correctly. Then adjusted the serial code to send bits at the right speed and format. The logging contents are now in hexdecimal with a CCITT CRC-16 computed to verify correct reception. Signed-off-by: Keith Packard --- src/micropeak/Makefile | 2 +- src/micropeak/ao_async.c | 43 ++++++++++++++++++++++++---- src/micropeak/ao_async.h | 6 ++++ src/micropeak/ao_log_micro.c | 55 +++++++++++++++++++++++++++++++++++- src/micropeak/ao_micropeak.c | 1 + 5 files changed, 99 insertions(+), 8 deletions(-) diff --git a/src/micropeak/Makefile b/src/micropeak/Makefile index 82944cb1..ff0a4499 100644 --- a/src/micropeak/Makefile +++ b/src/micropeak/Makefile @@ -50,7 +50,7 @@ IDPRODUCT=0 PRODUCT=MicroPeak-v0.1 PRODUCT_DEF=-DMICROPEAK CFLAGS = $(PRODUCT_DEF) -I. -I../attiny -I../core -I.. -I../drivers -CFLAGS += -g -mmcu=$(MCU) -Wall -Wstrict-prototypes -O3 -mcall-prologues -DATTINY +CFLAGS += -g -mmcu=$(MCU) -Wall -Wstrict-prototypes -O2 -mcall-prologues -DATTINY NICKLE=nickle diff --git a/src/micropeak/ao_async.c b/src/micropeak/ao_async.c index 04bba9e8..3556f54c 100644 --- a/src/micropeak/ao_async.c +++ b/src/micropeak/ao_async.c @@ -21,20 +21,51 @@ #define AO_ASYNC_BAUD 38400l #define AO_ASYNC_DELAY (uint8_t) (1000000l / AO_ASYNC_BAUD) +#define LED_PORT PORTB + +void +ao_async_start(void) +{ + LED_PORT |= (1 << AO_LED_SERIAL); +} + +void +ao_async_stop(void) +{ + LED_PORT &= ~(1 << AO_LED_SERIAL); +} + void ao_async_byte(uint8_t byte) { uint8_t b; uint16_t w; - /* start bit */ - - /* start data stop */ - w = 0x001 | (byte << 1) | 0x000; + /* start data stop */ + w = (0x000 << 0) | (byte << 1) | (0x001 << 9); + ao_arch_block_interrupts(); for (b = 0; b < 10; b++) { - ao_led_set((w & 1) << AO_LED_SERIAL); + uint8_t v = LED_PORT & ~(1 << AO_LED_SERIAL); + v |= (w & 1) << AO_LED_SERIAL; + LED_PORT = v; w >>= 1; - ao_delay_us(26); + + /* Carefully timed to hit around 9600 baud */ + asm volatile ("nop"); + asm volatile ("nop"); + + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); + asm volatile ("nop"); } + ao_arch_release_interrupts(); } diff --git a/src/micropeak/ao_async.h b/src/micropeak/ao_async.h index a06d2e1a..1b239712 100644 --- a/src/micropeak/ao_async.h +++ b/src/micropeak/ao_async.h @@ -18,6 +18,12 @@ #ifndef _AO_ASYNC_H_ #define _AO_ASYNC_H_ +void +ao_async_start(void); + +void +ao_async_stop(void); + void ao_async_byte(uint8_t byte); diff --git a/src/micropeak/ao_log_micro.c b/src/micropeak/ao_log_micro.c index 40a7a35d..d665efb5 100644 --- a/src/micropeak/ao_log_micro.c +++ b/src/micropeak/ao_log_micro.c @@ -49,6 +49,46 @@ ao_log_micro_data(void) } } +#define POLY 0x8408 + +static uint16_t +ao_log_micro_crc(uint16_t crc, uint8_t byte) +{ + uint8_t i; + + for (i = 0; i < 8; i++) { + if ((crc & 0x0001) ^ (byte & 0x0001)) + crc = (crc >> 1) ^ POLY; + else + crc = crc >> 1; + byte >>= 1; + } + return crc; +} + +static void +ao_log_hex_nibble(uint8_t b) +{ + if (b < 10) + ao_async_byte('0' + b); + else + ao_async_byte('a' - 10 + b); +} + +static void +ao_log_hex(uint8_t b) +{ + ao_log_hex_nibble(b>>4); + ao_log_hex_nibble(b&0xf); +} + +static void +ao_log_newline(void) +{ + ao_async_byte('\r'); + ao_async_byte('\n'); +} + void ao_log_micro_dump(void) { @@ -56,13 +96,26 @@ ao_log_micro_dump(void) uint16_t nbytes; uint8_t byte; uint16_t b; + uint16_t crc = 0xffff; ao_eeprom_read(N_SAMPLES_OFFSET, &n_samples, sizeof (n_samples)); + if (n_samples == 0xffff) + n_samples = 0; nbytes = STARTING_LOG_OFFSET + sizeof (uint16_t) * n_samples; + ao_async_start(); ao_async_byte('M'); ao_async_byte('P'); for (b = 0; b < nbytes; b++) { + if ((b & 0xf) == 0) + ao_log_newline(); ao_eeprom_read(b, &byte, 1); - ao_async_byte(byte); + ao_log_hex(byte); + crc = ao_log_micro_crc(crc, byte); } + ao_log_newline(); + crc = ~crc; + ao_log_hex(crc >> 8); + ao_log_hex(crc); + ao_log_newline(); + ao_async_stop(); } diff --git a/src/micropeak/ao_micropeak.c b/src/micropeak/ao_micropeak.c index 3bbc7eea..f579a09a 100644 --- a/src/micropeak/ao_micropeak.c +++ b/src/micropeak/ao_micropeak.c @@ -19,6 +19,7 @@ #include #include #include +#include static struct ao_ms5607_sample sample; static struct ao_ms5607_value value; -- 2.30.2