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#include <tft.h>
#include <tty.h>
#include <i2c.h>
#include <zeta.h>
#include <input.h>
void
uart_putchar(char c);
static inline void
enable_input_fifo(void)
{
}
static inline void
disable_input_fifo(void)
{
}
static inline void
init_pio(void)
{
// Control mode - i.e. no parallel port communication
port_b_ctrl = PIO_MODE_3;
// A, B and five keys as inputs
port_b_ctrl = 0x7F;
// Load interrupt vector
// port_b_ctrl = ISR_ADDRESS(port_b_isr_ptr);
// Interrupt word - interrupt if any pin goes low, mask follows
// port_b_ctrl = PIO_INT_CTRL(PIO_INT_EN | PIO_OR | PIO_LOW | PIO_MASK);
// Mask - 0 means to check line
// port_b_ctrl = 0x80;
/* port_a_ctrl = PIO_MODE_3; */
/* port_a_ctrl = 0x7C; */
/* // Load interrupt vector */
/* port_a_ctrl = ISR_ADDRESS(port_a_isr_ptr); */
/* port_a_ctrl = PIO_INT_CTRL(PIO_INT_EN | PIO_OR | PIO_HIGH | PIO_MASK); */
/* port_a_ctrl = 0x83; */
/* // SDA and SCL high */
/* port_a_data = 0x03; */
}
static inline void
init_ctc(void)
{
/* 200Hz clock */
ctc_channel_1 = CTC_CTRL(CTC_INT_BIT | CTC_PRESCALER_BIT
| CTC_TIME_CONST_BIT | CTC_RST_BIT);
ctc_channel_1 = 0;
/* 200Hz clock */
ctc_channel_2 = CTC_CTRL(CTC_INT_BIT | CTC_PRESCALER_BIT
| CTC_TIME_CONST_BIT | CTC_RST_BIT);
ctc_channel_2 = 0;
/* ctc_channel_3 = (CPU_FREQ / 256 / 144); */
ctc_channel_3 = CTC_CTRL(CTC_INT_BIT | CTC_PRESCALER_BIT
| CTC_TIME_CONST_BIT | CTC_RST_BIT);
ctc_channel_3 = 0; // 256
// Interrupt table for CTC
// Final address is (Ireg << 8) | ctc_isr_ptr | {00/01/10/11} | 0
ctc_channel_0 = ISR_ADDRESS(ctc0_isr_ptr);
}
static inline void
init_sio(void)
{
static const u8 sio_a_cfg[] = {
0b00011000, // Reset channel
4 , // wr4
0b01000100, // X16 clock (115200), one stop bit, no parity
1 , // wr1
SIO_RX_INT_MD0 | SIO_RX_INT_MD1, // interrupt on every Rx, no wait function
3 , // wr3
0b11000001, // enable Rx - 8 bit char
5 , // wr5
0b01101000 // enable Tx - 8 bit char
};
static const u8 sio_b_cfg[] = {
0b00011000, // Reset channel
2 , // load interrupt vector
ISR_ADDRESS(rx_isr_ptr) // int_table_rx
};
for (u8 i = 0; i < LENGTH(sio_a_cfg); ++i)
sio_a_ctrl = sio_a_cfg[i];
for (u8 i = 0; i < LENGTH(sio_b_cfg); ++i)
sio_b_ctrl = sio_b_cfg[i];
}
// copy code to ram, so function pointer is modifyable
static uint8_t tick = 0;
void
timer(void) __critical __interrupt(5)
{
static int prescale = 0;
if (++prescale == 150) {
prescale = 0;
tick = 1;
}
}
/* i2c_start_condition(); */
/* i2c_send(0xA0); */
/* i2c_send(0x00); */
/* i2c_send(0x00); */
/* i2c_restart_condition(); */
/* i2c_send(0xA1); */
/* b = i2c_recv(NACK); */
/* i2c_stop_condition(); */
void
main(void)
{
tft_init();
init_ctc();
init_pio();
init_sio();
// Interrupt mode 2
IM(2);
// Enable interrupts
EI;
// Boot menu
addstr("1) Programming mode\r\n");
addstr("2) Normal boot (default)\r\n");
addstr("3) Boot address 0xC000\r\n");
for (int i = 5; i > 0; --i) {
addch('\r');
addch(i + '0');
while (!tick) {
u8 keys = poll_keys();
if (!(keys & KEY2)) {
addch('\r');
bootloader();
}
if (!(keys & KEY3)) {
goto boot;
}
if (!(keys & KEY4)) {
// Definitely safe looking C code ...
void (*ptr)(void) = (void (*)(void))0xC000;
ptr();
}
}
DI;
tick = 0;
EI;
}
addch('\r');
boot:
addstr("Starting system ...\r\n");
// Load interrupt vector
port_b_ctrl = ISR_ADDRESS(port_b_isr_ptr);
// Interrupt word - interrupt if any pin goes low, mask follows
port_b_ctrl = PIO_INT_CTRL(PIO_INT_EN | PIO_OR | PIO_LOW | PIO_MASK);
// Mask - 0 means to check line
port_b_ctrl = 0x80;
_menu();
while (1)
;
}
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