Inital commit of stm32f4xx framework.

1 files changed, 829 insertions, 0 deletions

diff --git a/stm/main.c b/stm/main.c
new file mode 100644
index 000000000..2e7f2ec90
--- /dev/null
+++ b/stm/main.c
@@ -0,0 +1,829 @@
+#include <stm32f4xx.h>
+#include <stm32f4xx_rcc.h>
+#include "std.h"
+
+#include "font_petme128_8x8.h"
+
+void delay_ms(int ms);
+
+void impl02_c_version() {
+    int x = 0;
+    while (x < 400) {
+        int y = 0;
+        while (y < 400) {
+            volatile int z = 0;
+            while (z < 400) {
+                z = z + 1;
+            }
+            y = y + 1;
+        }
+        x = x + 1;
+    }
+}
+
+void set_bits(__IO uint32_t *addr, uint32_t shift, uint32_t mask, uint32_t value) {
+    uint32_t x = *addr;
+    x &= ~(mask << shift);
+    x |= (value << shift);
+    *addr = x;
+}
+
+void gpio_init() {
+    RCC->AHB1ENR |= RCC_AHB1ENR_CCMDATARAMEN | RCC_AHB1ENR_GPIOCEN | RCC_AHB1ENR_GPIOBEN | RCC_AHB1ENR_GPIOAEN;
+}
+
+#define PYB_LEDR_PORT (GPIOA)
+#define PYB_LEDR1_PORT_NUM (8)
+#define PYB_LEDR2_PORT_NUM (10)
+#define PYB_LEDG_PORT (GPIOC)
+#define PYB_LEDG1_PORT_NUM (4)
+#define PYB_LEDG2_PORT_NUM (5)
+
+void gpio_pin_init(GPIO_TypeDef *gpio, uint32_t pin, uint32_t moder, uint32_t otyper, uint32_t ospeedr, uint32_t pupdr) {
+    set_bits(&gpio->MODER, 2 * pin, 3, moder);
+    set_bits(&gpio->OTYPER, pin, 1, otyper);
+    set_bits(&gpio->OSPEEDR, 2 * pin, 3, ospeedr);
+    set_bits(&gpio->PUPDR, 2 * pin, 3, pupdr);
+}
+
+void gpio_pin_af(GPIO_TypeDef *gpio, uint32_t pin, uint32_t af) {
+    // set the AF bits for the given pin
+    // pins 0-7 use low word of AFR, pins 8-15 use high word
+    set_bits(&gpio->AFR[pin >> 3], 4 * (pin & 0x07), 0xf, af);
+}
+
+void mma_init() {
+    RCC->APB1ENR |= RCC_APB1ENR_I2C1EN; // enable I2C1
+    gpio_pin_init(GPIOB, 6 /* B6 is SCL */, 2 /* AF mode */, 1 /* open drain output */, 1 /* 25 MHz */, 0 /* no pull up or pull down */);
+    gpio_pin_init(GPIOB, 7 /* B7 is SDA */, 2 /* AF mode */, 1 /* open drain output */, 1 /* 25 MHz */, 0 /* no pull up or pull down */);
+    gpio_pin_af(GPIOB, 6, 4 /* AF 4 for I2C1 */);
+    gpio_pin_af(GPIOB, 7, 4 /* AF 4 for I2C1 */);
+
+    // get clock speeds
+    RCC_ClocksTypeDef rcc_clocks;
+    RCC_GetClocksFreq(&rcc_clocks);
+
+    // disable the I2C peripheral before we configure it
+    I2C1->CR1 &= ~I2C_CR1_PE;
+
+    // program peripheral input clock
+    I2C1->CR2 = 4; // no interrupts; 4 MHz (hopefully!) (could go up to 42MHz)
+
+    // configure clock control reg
+    uint32_t freq = rcc_clocks.PCLK1_Frequency / (100000 << 1); // want 100kHz, this is the formula for freq
+    I2C1->CCR = freq; // standard mode (speed), freq calculated as above
+
+    // configure rise time reg
+    I2C1->TRISE = (rcc_clocks.PCLK1_Frequency / 1000000) + 1; // formula for trise, gives maximum rise time
+
+    // enable the I2C peripheral
+    I2C1->CR1 |= I2C_CR1_PE;
+
+    // set START bit in CR1 to generate a start cond!
+}
+
+uint32_t i2c_get_sr() {
+    // must read SR1 first, then SR2, as the read can clear some flags
+    uint32_t sr1 = I2C1->SR1;
+    uint32_t sr2 = I2C1->SR2;
+    return (sr2 << 16) | sr1;
+}
+
+void mma_restart(uint8_t addr, int write) {
+    // send start condition
+    I2C1->CR1 |= I2C_CR1_START;
+
+    // wait for BUSY, MSL and SB --> Slave has acknowledged start condition
+    while ((i2c_get_sr() & 0x00030001) != 0x00030001) {
+    }
+
+    if (write) {
+        // send address and write bit
+        I2C1->DR = (addr << 1) | 0;
+        // wait for BUSY, MSL, ADDR, TXE and TRA
+        while ((i2c_get_sr() & 0x00070082) != 0x00070082) {
+        }
+    } else {
+        // send address and read bit
+        I2C1->DR = (addr << 1) | 1;
+        // wait for BUSY, MSL and ADDR flags
+        while ((i2c_get_sr() & 0x00030002) != 0x00030002) {
+        }
+    }
+}
+
+void mma_start(uint8_t addr, int write) {
+    // wait until I2C is not busy
+    while (I2C1->SR2 & I2C_SR2_BUSY) {
+    }
+
+    // do rest of start
+    mma_restart(addr, write);
+}
+
+void mma_send_byte(uint8_t data) {
+    // send byte
+    I2C1->DR = data;
+    // wait for TRA, BUSY, MSL, TXE and BTF (byte transmitted)
+    int timeout = 1000000;
+    while ((i2c_get_sr() & 0x00070084) != 0x00070084) {
+        if (timeout-- <= 0) {
+            printf("mma_send_byte timed out!\n");
+            break;
+        }
+    }
+}
+
+uint8_t mma_read_ack() {
+    // enable ACK of received byte
+    I2C1->CR1 |= I2C_CR1_ACK;
+    // wait for BUSY, MSL and RXNE (byte received)
+    while ((i2c_get_sr() & 0x00030040) != 0x00030040) {
+    }
+    // read and return data
+    uint8_t data = I2C1->DR;
+    return data;
+}
+
+uint8_t mma_read_nack() {
+    // disable ACK of received byte (to indicate end of receiving)
+    I2C1->CR1 &= (uint16_t)~((uint16_t)I2C_CR1_ACK);
+    // last byte should apparently also generate a stop condition
+    I2C1->CR1 |= I2C_CR1_STOP;
+    // wait for BUSY, MSL and RXNE (byte received)
+    while ((i2c_get_sr() & 0x00030040) != 0x00030040) {
+    }
+    // read and return data
+    uint8_t data = I2C1->DR;
+    return data;
+}
+
+void mma_stop() {
+    // send stop condition
+    I2C1->CR1 |= I2C_CR1_STOP;
+}
+
+void led_init() {
+    // set the output high (so LED is off)
+    PYB_LEDR_PORT->BSRRL = 1 << PYB_LEDR1_PORT_NUM;
+    PYB_LEDR_PORT->BSRRL = 1 << PYB_LEDR2_PORT_NUM;
+    PYB_LEDG_PORT->BSRRL = 1 << PYB_LEDG1_PORT_NUM;
+    PYB_LEDG_PORT->BSRRL = 1 << PYB_LEDG2_PORT_NUM;
+    // make it an open drain output
+    gpio_pin_init(PYB_LEDR_PORT, PYB_LEDR1_PORT_NUM, 1, 1, 0, 0);
+    gpio_pin_init(PYB_LEDR_PORT, PYB_LEDR2_PORT_NUM, 1, 1, 0, 0);
+    gpio_pin_init(PYB_LEDG_PORT, PYB_LEDG1_PORT_NUM, 1, 1, 0, 0);
+    gpio_pin_init(PYB_LEDG_PORT, PYB_LEDG2_PORT_NUM, 1, 1, 0, 0);
+}
+
+static void led_state(uint32_t led_port, int s) {
+    if (s == 0) {
+        // LED off, output is high
+        if (led_port == PYB_LEDR1_PORT_NUM || led_port == PYB_LEDR2_PORT_NUM) {
+            PYB_LEDR_PORT->BSRRL = 1 << led_port;
+        } else {
+            PYB_LEDG_PORT->BSRRL = 1 << led_port;
+        }
+    } else {
+        // LED on, output is low
+        if (led_port == PYB_LEDR1_PORT_NUM || led_port == PYB_LEDR2_PORT_NUM) {
+            PYB_LEDR_PORT->BSRRH = 1 << led_port;
+        } else {
+            PYB_LEDG_PORT->BSRRH = 1 << led_port;
+        }
+    }
+}
+
+#define PYB_USRSW_PORT (GPIOA)
+#define PYB_USRSW_PORT_NUM (13)
+
+void sw_init() {
+    // make it an input with pull-up
+    gpio_pin_init(PYB_USRSW_PORT, PYB_USRSW_PORT_NUM, 0, 0, 0, 1);
+}
+
+int sw_get() {
+    if (PYB_USRSW_PORT->IDR & (1 << PYB_USRSW_PORT_NUM)) {
+        // pulled high, so switch is not pressed
+        return 0;
+    } else {
+        // pulled low, so switch is pressed
+        return 1;
+    }
+}
+
+#define PYB_LCD_PORT        (GPIOA)
+#define PYB_LCD_CS1_PIN     (0)
+#define PYB_LCD_RST_PIN     (1)
+#define PYB_LCD_A0_PIN      (2)
+#define PYB_LCD_SCL_PIN     (3)
+#define PYB_LCD_SI_PIN      (4)
+
+static void lcd_comm_out(uint8_t i) {
+    delay_ms(0);
+    PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_CS1_PIN; // CS=0; enable
+    PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_A0_PIN; // A0=0; select instr reg
+    // send byte bigendian, latches on rising clock
+    for (uint32_t n = 0; n < 8; n++) {
+        delay_ms(0);
+        PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_SCL_PIN; // SCL=0
+        if ((i & 0x80) == 0) {
+            PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_SI_PIN; // SI=0
+        } else {
+            PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_SI_PIN; // SI=1
+        }
+        i <<= 1;
+        delay_ms(0);
+        PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_SCL_PIN; // SCL=1
+    }
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_CS1_PIN; // CS=1; disable
+
+    /*
+    in Python, native types:
+    CS1_PIN(const) = 0
+    n = int(0)
+    delay_ms(0)
+    PORT[word:BSRRH] = 1 << CS1_PIN
+    for n in range(0, 8):
+        delay_ms(0)
+        PORT[word:BSRRH] = 1 << SCL_PIN
+        if i & 0x80 == 0:
+            PORT[word:BSRRH] = 1 << SI_PIN
+        else:
+            PORT[word:BSRRL] = 1 << SI_PIN
+        i <<= 1
+        delay_ms(0)
+        PORT[word:BSRRL] = 1 << SCL_PIN
+    */
+}
+
+static void lcd_data_out(uint8_t i) {
+    delay_ms(0);
+    PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_CS1_PIN; // CS=0; enable
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_A0_PIN; // A0=1; select data reg
+    // send byte bigendian, latches on rising clock
+    for (uint32_t n = 0; n < 8; n++) {
+        delay_ms(0);
+        PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_SCL_PIN; // SCL=0
+        if ((i & 0x80) == 0) {
+            PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_SI_PIN; // SI=0
+        } else {
+            PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_SI_PIN; // SI=1
+        }
+        i <<= 1;
+        delay_ms(0);
+        PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_SCL_PIN; // SCL=1
+    }
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_CS1_PIN; // CS=1; disable
+}
+
+#define LCD_BUF_W (16)
+#define LCD_BUF_H (4)
+char lcd_buffer[LCD_BUF_W * LCD_BUF_H];
+int lcd_line;
+int lcd_column;
+int lcd_next_line;
+
+void lcd_print_strn(const char *str, unsigned int len) {
+    int redraw_min = lcd_line * LCD_BUF_W + lcd_column;
+    int redraw_max = redraw_min;
+    int did_new_line = 0;
+    for (; len > 0; len--, str++) {
+        // move to next line if needed
+        if (lcd_next_line) {
+            if (lcd_line + 1 < LCD_BUF_H) {
+                lcd_line += 1;
+            } else {
+                lcd_line = LCD_BUF_H - 1;
+                for (int i = 0; i < LCD_BUF_W * (LCD_BUF_H - 1); i++) {
+                    lcd_buffer[i] = lcd_buffer[i + LCD_BUF_W];
+                }
+                for (int i = 0; i < LCD_BUF_W; i++) {
+                    lcd_buffer[LCD_BUF_W * (LCD_BUF_H - 1) + i] = ' ';
+                }
+                redraw_min = 0;
+                redraw_max = LCD_BUF_W * LCD_BUF_H;
+            }
+            lcd_next_line = 0;
+            lcd_column = 0;
+            did_new_line = 1;
+        }
+        if (*str == '\n') {
+            lcd_next_line = 1;
+        } else if (lcd_column >= LCD_BUF_W) {
+            lcd_next_line = 1;
+            str -= 1;
+            len += 1;
+        } else {
+            lcd_buffer[lcd_line * LCD_BUF_W + lcd_column] = *str;
+            lcd_column += 1;
+            int max = lcd_line * LCD_BUF_W + lcd_column;
+            if (max > redraw_max) {
+                redraw_max = max;
+            }
+        }
+    }
+
+    int last_page = -1;
+    for (int i = redraw_min; i < redraw_max; i++) {
+        int page = i / LCD_BUF_W;
+        if (page != last_page) {
+            int offset = 8 * (i - (page * LCD_BUF_W));
+            lcd_comm_out(0xb0 | page); // page address set
+            lcd_comm_out(0x10 | ((offset >> 4) & 0x0f)); // column address set upper
+            lcd_comm_out(0x00 | (offset & 0x0f)); // column address set lower
+            last_page = page;
+        }
+        int chr = lcd_buffer[i];
+        if (chr < 32 || chr > 126) {
+            chr = 127;
+        }
+        const uint8_t *chr_data = &font_petme128_8x8[(chr - 32) * 8];
+        for (int i = 0; i < 8; i++) {
+            lcd_data_out(chr_data[i]);
+        }
+    }
+
+    if (did_new_line) {
+        delay_ms(200);
+    }
+}
+
+static void lcd_init() {
+    // set the outputs high
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_CS1_PIN;
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_RST_PIN;
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_A0_PIN;
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_SCL_PIN;
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_SI_PIN;
+    // make them push/pull outputs
+    gpio_pin_init(PYB_LCD_PORT, PYB_LCD_CS1_PIN, 1, 0, 0, 0);
+    gpio_pin_init(PYB_LCD_PORT, PYB_LCD_RST_PIN, 1, 0, 0, 0);
+    gpio_pin_init(PYB_LCD_PORT, PYB_LCD_A0_PIN, 1, 0, 0, 0);
+    gpio_pin_init(PYB_LCD_PORT, PYB_LCD_SCL_PIN, 1, 0, 0, 0);
+    gpio_pin_init(PYB_LCD_PORT, PYB_LCD_SI_PIN, 1, 0, 0, 0);
+
+    // init the LCD
+    delay_ms(1); // wait a bit
+    PYB_LCD_PORT->BSRRH = 1 << PYB_LCD_RST_PIN; // RST=0; reset
+    delay_ms(1); // wait for reset; 2us min
+    PYB_LCD_PORT->BSRRL = 1 << PYB_LCD_RST_PIN; // RST=1; enable
+    delay_ms(1); // wait for reset; 2us min
+    lcd_comm_out(0xa0); // ADC select, normal
+    lcd_comm_out(0xc8); // common output mode select, reverse
+    lcd_comm_out(0xa2); // LCD bias set, 1/9 bias
+    lcd_comm_out(0x2f); // power control set, 0b111=(booster on, vreg on, vfollow on)
+    lcd_comm_out(0x21); // v0 voltage regulator internal resistor ratio set, 0b001=small
+    lcd_comm_out(0x81); // electronic volume mode set
+    lcd_comm_out(0x34); // electronic volume register set, 0b110100
+    lcd_comm_out(0x40); // display start line set, 0
+    lcd_comm_out(0xaf); // LCD display, on
+
+    // clear display
+    for (int page = 0; page < 4; page++) {
+        lcd_comm_out(0xb0 | page); // page address set
+        lcd_comm_out(0x10); // column address set upper
+        lcd_comm_out(0x00); // column address set lower
+        for (int i = 0; i < 128; i++) {
+            lcd_data_out(0x00);
+        }
+    }
+
+    for (int i = 0; i < LCD_BUF_H * LCD_BUF_W; i++) {
+        lcd_buffer[i] = ' ';
+    }
+    lcd_line = 0;
+    lcd_column = 0;
+    lcd_next_line = 0;
+}
+
+void __fatal_error(const char *msg) {
+    lcd_print_strn("\nFATAL ERROR:\n", 14);
+    lcd_print_strn(msg, strlen(msg));
+
+    for (;;) {
+        led_state(PYB_LEDR1_PORT_NUM, 1);
+        led_state(PYB_LEDR2_PORT_NUM, 0);
+        delay_ms(150);
+        led_state(PYB_LEDR1_PORT_NUM, 0);
+        led_state(PYB_LEDR2_PORT_NUM, 1);
+        delay_ms(150);
+    }
+}
+
+#include "misc.h"
+#include "lexer.h"
+#include "mpyconfig.h"
+#include "parse.h"
+#include "compile.h"
+#include "runtime.h"
+
+/*
+py_obj_t pyb_delay(py_obj_t count) {
+    delay_ms(rt_get_int(count));
+    return py_const_none;
+}
+
+py_obj_t pyb_led(py_obj_t state) {
+    led_state(PYB_LEDG1_PORT_NUM, rt_is_true(state));
+    return state;
+}
+
+py_obj_t pyb_sw() {
+    if (sw_get()) {
+        return py_const_true;
+    } else {
+        return py_const_false;
+    }
+}
+*/
+
+#include "asmthumb.h"
+typedef void (*fun_t)();
+
+#include "ff.h"
+FATFS fatfs0;
+
+int main() {
+    // should disable JTAG
+
+    //qstr_init();
+    //rt_init();
+
+    gpio_init();
+    led_init();
+    sw_init();
+    lcd_init();
+
+    // print a message
+    printf(" micro py board\n");
+
+    // flash to indicate we are alive!
+    for (int i = 0; i < 2; i++) {
+        led_state(PYB_LEDR1_PORT_NUM, 1);
+        led_state(PYB_LEDR2_PORT_NUM, 0);
+        delay_ms(200);
+        led_state(PYB_LEDR1_PORT_NUM, 0);
+        led_state(PYB_LEDR2_PORT_NUM, 1);
+        delay_ms(200);
+    }
+
+    led_state(PYB_LEDR1_PORT_NUM, 0);
+    led_state(PYB_LEDR2_PORT_NUM, 0);
+    led_state(PYB_LEDG1_PORT_NUM, 0);
+    led_state(PYB_LEDG2_PORT_NUM, 0);
+
+    // get and print clock speeds
+    // SYSCLK=168MHz, HCLK=168MHz, PCLK1=42MHz, PCLK2=84MHz
+    /*
+    {
+        RCC_ClocksTypeDef rcc_clocks;
+        RCC_GetClocksFreq(&rcc_clocks);
+        printf("S=%lu H=%lu P1=%lu P2=%lu\n", rcc_clocks.SYSCLK_Frequency, rcc_clocks.HCLK_Frequency, rcc_clocks.PCLK1_Frequency, rcc_clocks.PCLK2_Frequency);
+        delay_ms(1000);
+    }
+    */
+
+    /*
+    extern int _sidata;
+    extern int _sdata;
+    extern int _edata;
+    extern int _sbss;
+    extern int _ebss;
+    delay_ms(2000);
+    printf("_sidata=%04x\n", _sidata);
+    printf("_sdata=%04x\n", _sdata);
+    printf("_edata=%04x\n", _edata);
+    printf("_sbss=%04x\n", _sbss);
+    printf("_ebss=%04x\n", _ebss);
+    //printf("sizeof(int)=%d\n", sizeof(int)); // 4
+    delay_ms(2000);
+    */
+
+    //printf("init;al=%u\n", m_get_total_bytes_allocated()); // 1600, due to qstr_init
+    //delay_ms(1000);
+
+    #if 0
+    // Python!
+    if (0) {
+        //const char *pysrc = "def f():\n  x=x+1\nprint(42)\n";
+        const char *pysrc =
+            // impl01.py
+            /*
+            "x = 0\n"
+            "while x < 400:\n"
+            "    y = 0\n"
+            "    while y < 400:\n"
+            "        z = 0\n"
+            "        while z < 400:\n"
+            "            z = z + 1\n"
+            "        y = y + 1\n"
+            "    x = x + 1\n";
+            */
+            // impl02.py
+            "#@micropython.native\n"
+            "def f():\n"
+            "    x = 0\n"
+            "    while x < 400:\n"
+            "        y = 0\n"
+            "        while y < 400:\n"
+            "            z = 0\n"
+            "            while z < 400:\n"
+            "                z = z + 1\n"
+            "            y = y + 1\n"
+            "        x = x + 1\n"
+            "f()\n";
+            /*
+            "print('in python!')\n"
+            "x = 0\n"
+            "while x < 4:\n"
+            "    pyb_led(True)\n"
+            "    pyb_delay(201)\n"
+            "    pyb_led(False)\n"
+            "    pyb_delay(201)\n"
+            "    x = x + 1\n"
+            "print('press me!')\n"
+            "while True:\n"
+            "    pyb_led(pyb_sw())\n";
+            */
+            /*
+            // impl16.py
+            "@micropython.asm_thumb\n"
+            "def delay(r0):\n"
+            "    b(loop_entry)\n"
+            "    label(loop1)\n"
+            "    movw(r1, 55999)\n"
+            "    label(loop2)\n"
+            "    subs(r1, r1, 1)\n"
+            "    cmp(r1, 0)\n"
+            "    bgt(loop2)\n"
+            "    subs(r0, r0, 1)\n"
+            "    label(loop_entry)\n"
+            "    cmp(r0, 0)\n"
+            "    bgt(loop1)\n"
+            "print('in python!')\n"
+            "@micropython.native\n"
+            "def flash(n):\n"
+            "    x = 0\n"
+            "    while x < n:\n"
+            "        pyb_led(True)\n"
+            "        delay(249)\n"
+            "        pyb_led(False)\n"
+            "        delay(249)\n"
+            "        x = x + 1\n"
+            "flash(20)\n";
+            */
+
+        py_lexer_t *lex = py_lexer_from_str_len("<>", pysrc, strlen(pysrc), false);
+
+        if (0) {
+            while (!py_lexer_is_kind(lex, PY_TOKEN_END)) {
+                py_token_show(py_lexer_cur(lex));
+                py_lexer_to_next(lex);
+                delay_ms(1000);
+            }
+        } else {
+            // nalloc=1740;6340;6836 -> 140;4600;496 bytes for lexer, parser, compiler
+            printf("lex; al=%u\n", m_get_total_bytes_allocated());
+            delay_ms(1000);
+            py_parse_node_t pn = py_parse(lex, 0);
+            //printf("----------------\n");
+            printf("pars;al=%u\n", m_get_total_bytes_allocated());
+            delay_ms(1000);
+            //parse_node_show(pn, 0);
+            py_compile(pn);
+            printf("comp;al=%u\n", m_get_total_bytes_allocated());
+            delay_ms(1000);
+
+            if (1) {
+                // execute it!
+
+                // add some functions to the python namespace
+                rt_store_name(qstr_from_str_static("pyb_delay"), rt_make_function_1(pyb_delay));
+                rt_store_name(qstr_from_str_static("pyb_led"), rt_make_function_1(pyb_led));
+                rt_store_name(qstr_from_str_static("pyb_sw"), rt_make_function_0(pyb_sw));
+
+                py_obj_t module_fun = rt_make_function_from_id(1);
+
+                led_state(PYB_LEDG1_PORT_NUM, 1);
+                delay_ms(100);
+                led_state(PYB_LEDG1_PORT_NUM, 0);
+                py_obj_t ret = rt_call_function_0(module_fun);
+                led_state(PYB_LEDG1_PORT_NUM, 1);
+                delay_ms(100);
+                led_state(PYB_LEDG1_PORT_NUM, 0);
+
+                printf("done! got: ");
+                py_obj_print(ret);
+                printf("\n");
+                delay_ms(1000);
+                printf("nalloc=%u\n", m_get_total_bytes_allocated());
+                delay_ms(1000);
+            }
+        }
+    }
+    #endif
+
+    // benchmark C version of impl02.py
+    if (0) {
+        led_state(PYB_LEDG1_PORT_NUM, 1);
+        delay_ms(100);
+        led_state(PYB_LEDG1_PORT_NUM, 0);
+        impl02_c_version();
+        led_state(PYB_LEDG1_PORT_NUM, 1);
+        delay_ms(100);
+        led_state(PYB_LEDG1_PORT_NUM, 0);
+    }
+
+    // MMA testing
+    if (0) {
+        printf("1");
+        mma_init();
+        printf("2");
+        mma_start(0x4c, 1);
+        printf("3");
+        mma_send_byte(0);
+        printf("4");
+        mma_stop();
+        printf("5");
+        mma_start(0x4c, 1);
+        printf("6");
+        mma_send_byte(0);
+        printf("7");
+        mma_restart(0x4c, 0);
+        for (int i = 0; i <= 0xa; i++) {
+            int data;
+            if (i == 0xa) {
+                data = mma_read_nack();
+            } else {
+                data = mma_read_ack();
+            }
+            printf(" %02x", data);
+        }
+        printf("\n");
+
+        mma_start(0x4c, 1);
+        mma_send_byte(7); // mode
+        mma_send_byte(1); // active mode
+        mma_stop();
+
+        for (;;) {
+            delay_ms(500);
+
+            mma_start(0x4c, 1);
+            mma_send_byte(0);
+            mma_restart(0x4c, 0);
+            for (int i = 0; i <= 3; i++) {
+                int data;
+                if (i == 3) {
+                    data = mma_read_nack();
+                    printf(" %02x\n", data);
+                } else {
+                    data = mma_read_ack() & 0x3f;
+                    if (data & 0x20) {
+                        data |= 0xc0;
+                    }
+                    printf(" % 2d", data);
+                }
+            }
+        }
+    }
+
+    // fatfs testing
+    if (1) {
+        FRESULT res = f_mount(&fatfs0, "0:", 1);
+        if (res == FR_OK) {
+            printf("mount success\n");
+        } else if (res == FR_NO_FILESYSTEM) {
+            res = f_mkfs("0:", 0, 0);
+            if (res == FR_OK) {
+                printf("mkfs success\n");
+            } else {
+                printf("mkfs fail %d\n", res);
+            }
+        } else {
+            printf("mount fail %d\n", res);
+        }
+
+        // write a file
+        if (0) {
+            FIL fp;
+            f_open(&fp, "0:/boot.py", FA_WRITE | FA_CREATE_ALWAYS);
+            UINT n;
+            f_write(&fp, "# this is boot.py\n", 18, &n);
+            printf("wrote %d\n", n);
+            f_close(&fp);
+        }
+
+        // read a file
+        if (1) {
+            FIL fp;
+            f_open(&fp, "0:/boot.py", FA_READ);
+            UINT n;
+            char buf[20];
+            f_read(&fp, buf, 18, &n);
+            buf[n + 1] = 0;
+            printf("read %d\n%s", n, buf);
+            f_close(&fp);
+        }
+
+        DWORD nclst;
+        FATFS *fatfs;
+        f_getfree("0:", &nclst, &fatfs);
+        printf("free=%d\n", nclst * fatfs->csize * 512);
+
+    }
+
+    // SD card testing
+    if (0) {
+        //sdio_init();
+    }
+
+    // USB VCP testing
+    if (0) {
+        //usb_vcp_init();
+    }
+
+    // USB MSC testing
+    if (1) {
+        void usb_msc_init();
+        usb_msc_init();
+    }
+
+    int i = 0;
+    int n = 0;
+
+    for (;;) {
+        delay_ms(10);
+        if (sw_get()) {
+            led_state(PYB_LEDR1_PORT_NUM, 1);
+            led_state(PYB_LEDG1_PORT_NUM, 0);
+            i = 1 - i;
+            if (i) {
+                printf(" angel %05x.\n", n);
+                //usb_vcp_send("hello!\r\n", 8);
+            } else {
+                printf(" mishka %4u.\n", n);
+                //usb_vcp_send("angel!\r\n", 8);
+            }
+            n += 1;
+        } else {
+            led_state(PYB_LEDR1_PORT_NUM, 0);
+            led_state(PYB_LEDG1_PORT_NUM, 1);
+        }
+    }
+
+    return 0;
+}
+
+/*
+void testf() {
+    testf(1, 2, 3);
+    testf(1, 2, 3, 4);
+    testf(1, 2, 3, 4, 5);
+    testf(1, 2, 3, 4, 5, 6);
+    testf(1, 2, 3, 4, 5, 6, 7);
+}
+
+int testg(int a, int b, int c, int d, int e) {
+    return a + b + c + d + testh(e);
+}
+
+int testh(int x, byte *y) {
+    return x + (y[-2] << 2);
+}
+*/
+
+/*
+void print_int(int x, int y, int z, int zz) {
+    printf("I %x %x %x %x", x, y, z, zz);
+    byte* ptr = (byte*)z;
+    printf("\nP %02x %02x %02x %02x", ptr[-4], ptr[-3], ptr[-2], ptr[-1]);
+    for (;;) {
+    }
+}
+void print_int_0(int x) { printf("P0 %x", x); }
+void print_int_1(int x) { printf("P1 %x", x); }
+void print_int_2(int x) { printf("P2 %x", x); }
+void print_int_3(int x) { printf("P3 %x", x); }
+void print_int_4(int x) { printf("P4 %x", x); }
+
+typedef struct _b_t {
+    void (*m1)(void*, int);
+    void (*m2)(void*, int);
+} b_t;
+typedef struct _a_t {
+    b_t *b;
+} a_t;
+void b_m1(b_t*, int);
+void b_m2(b_t*, int);
+void f1(a_t *a) {
+    a->b->m1(a->b, 2);
+    a->b->m2(a->b, 4);
+    b_m1(a->b, 2);
+    b_m2(a->b, 4);
+}
+void b_m1(b_t *b, int x) {
+    b->m1(b, x);
+}
+*/