initial commit

This commit is contained in:
Olaf Rempel 2017-05-25 11:15:22 +02:00
commit 9e69670da0
3 changed files with 430 additions and 0 deletions

6
.gitignore vendored Normal file
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*.o
*.elf
*.bin
*.hex
*.lst
*.map

56
Makefile Normal file
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PRG = epromsim
OBJ = main.o
MCU_TARGET = attiny2313
OPTIMIZE = -Os
#AVRDUDE_PROG = -c avr910 -b 115200 -P /dev/ispprog
AVRDUDE_PROG = -c dragon_isp -P usb
AVRDUDE_MCU = attiny2313
DEFS =
LIBS =
# Override is only needed by avr-lib build system.
override CFLAGS = -g -Wall $(OPTIMIZE) -mmcu=$(MCU_TARGET) $(DEFS)
override LDFLAGS = -Wl,-Map,$(PRG).map
CC = avr-gcc
OBJCOPY = avr-objcopy
OBJDUMP = avr-objdump
SIZE = avr-size
all: $(PRG).elf lst text
$(SIZE) -x -A $(PRG).elf
$(PRG).elf: $(OBJ)
$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS)
%.o: %.c $(MAKEFILE_LIST)
$(CC) $(CFLAGS) -c $< -o $@
clean:
rm -rf *.o $(PRG).lst $(PRG).map $(PRG).elf $(PRG).hex $(PRG).bin
lst: $(PRG).lst
%.lst: %.elf
$(OBJDUMP) -h -S $< > $@
text: hex bin
hex: $(PRG).hex
bin: $(PRG).bin
%.hex: %.elf
$(OBJCOPY) -j .text -j .data -O ihex $< $@
%.bin: %.elf
$(OBJCOPY) -j .text -j .data -O binary $< $@
install: text
avrdude $(AVRDUDE_PROG) -p $(AVRDUDE_MCU) -V -U flash:w:$(PRG).hex
fuses:
avrdude $(AVRDUDE_PROG) -p $(AVRDUDE_MCU) -U efuse:w:0xff:m
avrdude $(AVRDUDE_PROG) -p $(AVRDUDE_MCU) -U hfuse:w:0xdb:m
avrdude $(AVRDUDE_PROG) -p $(AVRDUDE_MCU) -U lfuse:w:0xff:m

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main.c Normal file
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/***************************************************************************
* Copyright (C) 04/2013 by Olaf Rempel *
* razzor@kopf-tisch.de *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; version 2 of the License, *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the *
* Free Software Foundation, Inc., *
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
***************************************************************************/
#include <avr/io.h>
#include <avr/interrupt.h>
#define F_CPU 11059200
#include <util/delay.h>
/*
* attiny2313
* lfuse: 0xff (ext. crystal, slow rising power, max startup time)
* hfuse: 0xdb (2.7V BOD)
* efuse: 0xff (self Prog enabled)
*
* PB0 -> NC
* PB1 -> reset-out
* PB2 -> /WR SRAM
* PB3 -> SRCK (shift register clock)
* PB4 -> SER (shift register input)
* PB5 -> CCK (counter clock)
* PB6 -> RCK (counter and shift register store clock)
* PB7 -> /OE (output enable counter, shift register, reset-out, A16)
* PD0 <- RXD
* PD1 -> TXD
* PD2 <- /PowerFail
* PD3 -> A16
* PD4 -> /LED_GN
* PD5 -> /LED_RT
* PD6 -> /OE (output enable RAM and address buffer, counter clear)
*/
#define RESET_OUT PORTB1
#define nRAM_WR PORTB2
#define SREG_CLK PORTB3
#define SREG_DAT PORTB4
#define CNT_CLK PORTB5
#define REG_STORE PORTB6
#define nEMU_EN PORTB7
#define RXD PORTD0
#define TXD PORTD1
#define nPOWERFAIL PORTD2
#define EMU_A16 PORTD3
#define nLED_GN PORTD4
#define nLED_RT PORTD5
#define nTARGET_EN PORTD6
#define BAUDRATE 115200
#define UART_CALC_BAUDRATE(baudRate) (((uint32_t)F_CPU) / (((uint32_t)baudRate)*16) -1)
struct _globdata {
uint8_t address_mask;
uint8_t reset_polarity;
};
static struct _globdata gdata = { 0 };
/* *************************************************************************
* send one byte to UART
* ************************************************************************* */
static void ser_send(uint8_t data)
{
loop_until_bit_is_set(UCSRA, UDRIE);
UDR = data;
} /* ser_send */
/* *************************************************************************
* receive one byte from UART
* ************************************************************************* */
static uint8_t ser_recv(void)
{
loop_until_bit_is_set(UCSRA, RXC);
return UDR;
} /* ser_recv */
/* *************************************************************************
* shift one byte out to register (LSB first)
* ************************************************************************* */
static void shift_data(uint8_t data)
{
uint8_t mask;
for (mask = 0x01; mask != 0; mask <<= 1) {
if (data & mask) {
PORTB |= (1<<SREG_DAT);
} else {
PORTB &= ~(1<<SREG_DAT);
}
/* positive edge clocks in data */
PORTB |= (1<<SREG_CLK);
PORTB &= ~(1<<SREG_CLK);
}
} /* shift_data */
/* *************************************************************************
* store pulse for register and counter
* ************************************************************************* */
static void store_pulse(void)
{
/* positive edge transfers data to output buffer */
PORTB |= (1<<REG_STORE);
PORTB &= ~(1<<REG_STORE);
} /* store_pulse */
/* *************************************************************************
* write pulse for SRAM and increment counter
* ************************************************************************* */
static void write_inc_pulse(void)
{
/* positive edge clocks in data */
PORTB &= ~(1<<nRAM_WR);
PORTB |= (1<<nRAM_WR);
/* positive edge increments counter */
PORTB |= (1<<CNT_CLK);
PORTB &= ~(1<<CNT_CLK);
} /* write_inc_pulse */
/* *************************************************************************
* switch access to RAM between emulator and target
* ************************************************************************* */
static void do_reset(uint8_t enable)
{
if (enable) {
/* switch RAM access to EMU */
PORTD |= (1<<nTARGET_EN);
PORTD &= ~(1<<nLED_RT);
PORTB &= ~(1<<nEMU_EN);
} else {
/* set eprom address line mask */
shift_data(gdata.address_mask);
shift_data(0x00);
store_pulse();
/* switch RAM access to TARGET */
PORTB |= (1<<nEMU_EN);
PORTD &= ~(1<<nTARGET_EN);
PORTD |= (1<<nLED_RT);
}
/* set RESET_OUT */
if (enable ^ gdata.reset_polarity) {
PORTB &= ~(1<<RESET_OUT);
} else {
PORTB |= (1<<RESET_OUT);
}
} /* do_reset */
/* *************************************************************************
* configures number of addresslines and loads data from UART into RAM
* ************************************************************************* */
static void do_load(uint8_t type, uint32_t length)
{
uint32_t size;
switch (type) {
case 0x02: /* 2716 - 2kB */
size = 0x0800;
gdata.address_mask = 0x00;
break;
case 0x04: /* 2732 - 4kB */
size = 0x1000;
gdata.address_mask = 0x80;
break;
case 0x08: /* 2764 - 8kB */
size = 0x2000;
gdata.address_mask = 0xC0;
break;
case 0x10: /* 27128 - 16kB */
size = 0x4000;
gdata.address_mask = 0xE0;
break;
case 0x20: /* 27256 - 32kB */
size = 0x8000;
gdata.address_mask = 0xF0;
break;
case 0x40: /* 27512 - 64kB */
size = 0x10000;
gdata.address_mask = 0xF8;
break;
default:
case 0x80: /* 27010 - 128kB */
size = 0x20000;
gdata.address_mask = 0xFC;
break;
}
do_reset(1);
uint32_t i;
uint8_t data;
for (i = 0; i < size; i++) {
if (i > 0xFFFF) {
PORTD |= (1<<EMU_A16);
} else {
PORTD &= ~(1<<EMU_A16);
}
data = (i < length) ? ser_recv() : 0xFF;
shift_data(data);
store_pulse();
write_inc_pulse();
}
do_reset(0);
} /* do_load */
/* *************************************************************************
* clears whole RAM (writes 0xFF)
* ************************************************************************* */
static void do_clear(void)
{
do_reset(1);
shift_data(0xFF);
uint16_t i = 0xFFFF;
PORTD &= ~(1<<EMU_A16);
do {
store_pulse();
write_inc_pulse();
} while (i--);
PORTD |= (1<<EMU_A16);
do {
store_pulse();
write_inc_pulse();
} while (i--);
do_reset(0);
} /* do_clear */
#if 0
/* Powerfail / Wakeup */
ISR(INT0_vect)
{
if (1) {
/*
* Power Fail:
* - enable RESET_OUT
* - disable nTARGET_EN
* - enable rising edge INT0 (nPOWERFAIL)
* - disable pullups
* - put MCU in standby
*/
do_reset(1);
/* disable green LED */
PORTD |= (1<<nLED_GN);
} else {
/*
* Power Restore:
* - enable pullups
* - enable falling edge INT0 (nPOWERFAIL)
* - enable nTARGET_EN again
* - disable RESET_OUT
*/
/* enable green LED */
PORTD &= ~(1<<nLED_GN);
do_reset(0);
}
}
#endif
int main(void) __attribute__ ((noreturn));
int main(void)
{
DDRB = 0xFF;
PORTB = (1<<nRAM_WR) | (1<<nEMU_EN);
DDRD = ~((1<<RXD) | (1<<nPOWERFAIL));
PORTD = (1<<RXD) | (1<<nPOWERFAIL) | (1<<nLED_GN) | (1<<nLED_RT) | (1<<nTARGET_EN);
/* enable UART 115200,8n1 */
UBRRH = (UART_CALC_BAUDRATE(BAUDRATE)>>8) & 0xFF;
UBRRL = (UART_CALC_BAUDRATE(BAUDRATE) & 0xFF);
UCSRC = (1<<UCSZ1) | (1<<UCSZ0);
UCSRB = (1<<RXEN) | (1<<TXEN);
#if 0
/* powerfail: detect falling edge on INT0 */
MCUCR = (1<<ISC01);
GIMSK = (1<<INT0);
sei();
#endif
/* enable LED and reset Counter */
PORTD &= ~((1<<nLED_GN) | (1<<nTARGET_EN));
/* init RAM */
gdata.address_mask = 0x3F;
do_clear();
while (1) {
uint8_t cmd = ser_recv();
switch (cmd) {
case 'p': /* low active reset */
gdata.reset_polarity = 0;
ser_send('\n');
break;
case 'P': /* high active reset */
gdata.reset_polarity = 1;
ser_send('\n');
break;
case 'r': /* reset pulse */
do_reset(1);
_delay_ms(10);
do_reset(0);
ser_send('\n');
break;
case 'l': /* load eprom content */
{
uint8_t type = ser_recv();
uint32_t length = (uint32_t)ser_recv() << 16;
length |= ser_recv() << 8;
length |= ser_recv();
do_load(type, length);
}
break;
default:
ser_send('?');
break;
}
}
}