LED matrix (HUB-75 type) - arduino

Question

I'm trying to make the 64x64 LED matrix work without libraries. Started driving it with STM32F103C8T6 chip figured out the problem and tried ATmega328 instead, but nothing changed.
The problem is when I'm trying to lit a LED on specified address it actually lights up with almost 0 brightness, but the LED directly under it (on the next address) lights up with full brightness.
I cut the code to a minimum.
#define CLK 0
#define LAT 1
#define R1 2
uint16_t data [64][4];
void shiftOutLed (void);
int main () {
data [0][0] = 0x0001;
data [0][2] = 0x1800;
DDRC |= 0x0F; //pin 0 - A, pin 1 - B, pin 2 - C, pin3 - D
DDRB |= 0x03; // pin 0 - CLK, pin 1 - LAT
DDRD |= 0x04; // pin 2 - R1
while (1){
shiftOutLed ();
}
}
void shiftOutLed (void){
for (uint8_t _addr = 0; _addr < 16; _addr++){
PORTC &= 0xF0;
PORTC |= _addr;
for (uint8_t _byte = 0; _byte < 4; _byte++){
for (uint8_t _bit = 0; _bit < 16; _bit++){
if (data[_addr][_byte] & (1 << _bit)) PORTD |= (1 << R1);
else PORTD &= ~(1 << R1);
PORTB |= (1 << CLK);
PORTB &= ~(1 << CLK);
}
}
PORTB |= (1 << LAT);
PORTB &= ~(1 << LAT);
PORTD &= ~(1 << R1);
}
}
When I modify the code introducing delays while clocking and latching every bit LEDs light up in right row.

Answer 1

Seems like the matrix needs the address set after clocking the entire row
#define CLK 0
#define LAT 1
#define R1 2
uint16_t data [64][4];
void shiftOutLed (void);
int main () {
data [0][0] = 0x0001;
data [0][2] = 0x1800;
DDRC |= 0x0F; //pin 0 - A, pin 1 - B, pin 2 - C, pin3 - D
DDRB |= 0x03; // pin 0 - CLK, pin 1 - LAT
DDRD |= 0x04; // pin 2 - R1
while (1){
shiftOutLed ();
}
}
void shiftOutLed (void){
for (uint8_t _addr = 0; _addr < 16; _addr++){
PORTC &= 0xF0;
for (uint8_t _byte = 0; _byte < 4; _byte++){
for (uint8_t _bit = 0; _bit < 16; _bit++){
if (data[_addr][_byte] & (1 << _bit)) PORTD |= (1 << R1);
else PORTD &= ~(1 << R1);
PORTB |= (1 << CLK);
PORTB &= ~(1 << CLK);
}
}
PORTC |= _addr;
PORTB |= (1 << LAT);
PORTB &= ~(1 << LAT);
PORTD &= ~(1 << R1);
}
}
Now it works