diff --git a/radio/nrf24L01/nrf-ftdi-ring.c b/radio/nrf24L01/nrf-ftdi-ring.c
index b8d37f1880e1b5eceb25b487e3d233366be14972..62b5f7230ec16be7d9dbffdc60b043a8d6c29460 100644
--- a/radio/nrf24L01/nrf-ftdi-ring.c
+++ b/radio/nrf24L01/nrf-ftdi-ring.c
@@ -69,6 +69,7 @@ uint8_t read_register(uint8_t reg){
return temp;
}
void write_register(uint8_t reg, uint8_t val){
+ //must be in standby mode before calling this function!
PORTC.OUTCLR = SS_BM; //SS low
_delay_us(1);
SPIC.DATA = W_REGISTER | reg; while(!(SPIC.STATUS & SPI_IF_bm)) {};
@@ -77,18 +78,18 @@ void write_register(uint8_t reg, uint8_t val){
_delay_us(1);
}
-
USART_data_t USART_data;
uint8_t token = 0; //token to pass
uint8_t tempval = 0;
const int pll_delay_us = 130;
+const int ce_delay_us = 10;
void check_registers(uint8_t id){
- //debug only
+ //for debug only
//enter standby so we can write to configuration register.
PORTC.OUTCLR = CE_BM;
- _delay_us(10);
+ _delay_us(ce_delay_us);
PORTC.OUTCLR = SS_BM; //SS low
_delay_us(10);
@@ -104,63 +105,16 @@ void check_registers(uint8_t id){
usart_send_byte(&USART_data,config);
usart_send_byte(&USART_data,token);
usart_send_byte(&USART_data,10);
-
- //interrupts
- /*if (!(PORTC.IN & IRQ_BM)){
- usart_send_byte(&USART_data,1);
- }
- //clear interrupt on MAX_RT
- PORTC.OUTCLR = SS_BM; //SS low
- _delay_ms(1);
- SPIC.DATA = W_REGISTER | STATUS; while(!(SPIC.STATUS & SPI_IF_bm)) {};
- SPIC.DATA |= MAX_RT; while(!(SPIC.STATUS & SPI_IF_bm)) {}; //write 1 to MAX_RT bit
- PORTC.OUTSET = SS_BM; //SS high
- _delay_ms(1);
- //interrupts
- if (!(PORTC.IN & IRQ_BM)){
- usart_send_byte(&USART_data,2);
- }*/
}
-// nRF24L01+ must be in a standby or power down mode before writing to the configuration registers.
-
-//overview
-// - turn off autoretransmit
-// - MAX_RT interrupts on IRQ
-// - set interrupt service routine on rising edge of IRQ (RX_DR)
-// - set interrupt service routing on USART RX
-// - enter RX mode PRIM_RX = 1 (SPI transaction), CE = 1
-// - When IRQ interupt,
-// - enter standby (CE=0)
-// - read payload (SPI transaction)
-// - process data and put result in TX fifo
-// - enter TX (PRIM_RX=0, CE=1 for more than 10 us) (130us)
-// - clear IRQ by writing 1 to STATUS register RX_DR bit. (SPI transaction)
-// - set CE=0 so we return to Standby when finished transmitting
-// - set PRIM_RX=1 (SPI transaction). can we only do this from standby? (130us)
-// - When USART interrupt,
-// - enter standby (CE=0)
-// - put token in TX fifo
-// - enter TX (PRIM_RX=0, CE=1 for more than 10 us)
-// - set CE=0 so we return to Standby when finished transmitting
-// - set PRIM_RX=1 (SPI transaction) to enter RX can we only do this from standby? (130us)
-
-//experiments
-// RF_SETUP, RF_DR_LOW, RF_DR_HIGH. Default RF data rate is 250kbps ( 4 us per byte ).
-// It can also be 1 Mbps (1 us per byte) and 2 Mbps (.5 us per byte)
-// increase SPI rate. right now its running at clkper/128 = sysclk/128 = 250 kHz (4 us per byte)
-
-
void rx_from_standby(){
- //enter standby so we can write to configuration register.
- PORTC.OUTCLR = CE_BM;
- _delay_us(10); //should be 10?
- //enter RX mode: set PRIM_RX = 1
- tempval = read_register(CONFIG);
- write_register(CONFIG, tempval | PRIM_RX)
+ //call this from standby to enter rx mode
+ //tempval = read_register(CONFIG);
+ //write_register(CONFIG, tempval | PRIM_RX);
+ write_register(CONFIG, 0x13); //replaces the spi read, but doesn't really speed things up much...
//set CE for at least 10 us
PORTC.OUTSET = CE_BM;
- _delay_us(10); //should be 10?
+ //_delay_us(ce_delay_us); //is this necessary?
//wait for pll to settle
_delay_us(pll_delay_us);
}
@@ -200,9 +154,9 @@ void setup(){
SPIC.INTCTRL = SPI_INTLVL_OFF_gc;
PORTC.DIRSET = PIN5_bm | PIN7_bm; //mosi and sck as outputs
PORTC.OUTSET = SS_BM; //SS high
-
_delay_ms(5); //warm up
+ //nrf config
//turn off auto-retransmit
write_register(SETUP_RETR,0);
//turn off disable auto-acknowledge
@@ -229,76 +183,83 @@ void setup(){
_delay_ms(1); //give time to start up
// and mask MAX_RT interrupts on IRQ
tempval = read_register(CONFIG);
- write_register(CONFIG,tempval | MAX_RT)
+ write_register(CONFIG,tempval | MAX_RT);
//clear all interrupts
tempval = read_register(STATUS);
- write_register(STATUS,tempval | MAX_RT | RX_DR | TX_DS)
+ write_register(STATUS,tempval | MAX_RT | RX_DR | TX_DS);
_delay_ms(1);
sei();
- rx_from_standby();
+ //enter standby so we can write to configuration register.
+ PORTC.OUTCLR = CE_BM;
+ _delay_us(ce_delay_us);
+ rx_from_standby(); //enter rx mode
}
-void send_token(){
- //transition from RX to standby1 (CE=0)
- PORTC.OUTCLR = CE_BM;
- _delay_us(10);
+
+void send_token(){
+ //call this from standby1
//put token in tx fifo
PORTC.OUTCLR = SS_BM; //SS low
_delay_us(1);
SPIC.DATA = W_TX_PAYLOAD; while(!(SPIC.STATUS & SPI_IF_bm)) {};
- SPIC.DATA = token; while(!(SPIC.STATUS & SPI_IF_bm)) {};
+ tempval = SPIC.DATA; //get status while we have it
+ SPIC.DATA = 0; while(!(SPIC.STATUS & SPI_IF_bm)) {};
PORTC.OUTSET = SS_BM; //SS high
_delay_us(1);
- tempval = read_register(CONFIG);
- write_register(CONFIG, tempval & (~PRIM_RX))
- //pulse CE for at least 10 us
- PORTC.OUTSET = CE_BM; _delay_us(10); PORTC.OUTCLR = CE_BM;
+ //tempval = read_register(CONFIG);
+ write_register(CONFIG, tempval & (~PRIM_RX));
+ //pulse CE
+ PORTC.OUTSET = CE_BM; _delay_us(ce_delay_us); PORTC.OUTCLR = CE_BM;
//wait for pll to settle
_delay_us(pll_delay_us);
//wait until transmit complete
while( PORTC.IN & IRQ_BM ){}
//clear IRQ -- need to be in standby.
tempval = read_register(STATUS);
- write_register(STATUS, tempval | TX_DS)
+ write_register(STATUS, tempval | TX_DS);
+ //enter standby so we can write to configuration register.
rx_from_standby(); //return to RX mode
}
void read_token(){
+ //call this from rx
//get token from rx fifo
PORTC.OUTCLR = SS_BM; //SS low
_delay_us(1);
SPIC.DATA = R_RX_PAYLOAD; while(!(SPIC.STATUS & SPI_IF_bm)) {};
- SPIC.DATA = 0; while(!(SPIC.STATUS & SPI_IF_bm)) {};
+ tempval = SPIC.DATA; //get status while we have it
+ SPIC.DATA = 0; while(!(SPIC.STATUS & SPI_IF_bm)) {};
token = SPIC.DATA;
PORTC.OUTSET = SS_BM; //SS high
_delay_us(1);
//transition from RX to standby1 (CE=0)
PORTC.OUTCLR = CE_BM;
- _delay_us(10);
+ _delay_us(ce_delay_us);
//clear IRQ
- tempval = read_register(STATUS);
- write_register(STATUS, tempval | RX_DR)
+ write_register(STATUS, tempval | RX_DR);
//check_registers(66);
}
int main(void) {
setup();
while(1){
- //should be in rx mode here.
if ( !(PORTC.IN & IRQ_BM)){
read_token(); //in standby
- token = 1-token; //transform token
+ token += 1; //increment token
//check_registers(65);
send_token();
}
- //when we get signal from usart, send a token on nrf
+ //we use a signal on the usart to start the oscillation.
if (USART_RXBufferData_Available(&USART_data)) {
USART_RXBuffer_GetByte(&USART_data); //clear usart buffer so we only fire once.
+ //transition from RX to standby1 (CE=0)
+ PORTC.OUTCLR = CE_BM;
+ _delay_us(ce_delay_us);
send_token();
//check_registers(64);
}
diff --git a/radio/nrf24L01/ring.png b/radio/nrf24L01/ring.png
index febd3532de00111619867f96363154ff7b43b7b9..5dead4cc1a597751dfbf060b850f6686fcac480e 100755
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diff --git a/radio/nrf24L01/ring2.png b/radio/nrf24L01/ring2.png
new file mode 100755
index 0000000000000000000000000000000000000000..c14e4aa21098978663438c43c5b15ee562bb06d3
Binary files /dev/null and b/radio/nrf24L01/ring2.png differ