I have a WT32-ETH01 dev board with an RFM73 radio transceiver attached, I need help using the RFM73 from my C code.
There are various working C++ class based libraries for the RFM73 - both arduino and ESP-IDF.
But my application is a C application.
The RFM73 is quite old and many links for documentation/datasheets/examples are now dead.
I downloaded the RFM73 C library from www.voti.nl using the 'wayback machine':
http://web.archive.org/web/201501032126 ... :80/rfm73/
RFM73 C library contains rf73.h and rfm73.c and is "not adapted for a specific platform".
It requires me to create rf73-config.h and in that file define some macros: "you must provide an rfm73-config.h file that declares macro's that initialize and access the I/O pins, and for delaying a specified number of microseconds and milliseconds".
I also downloaded the 'C library adapted for DB038', this contains a rf73-config.h for the PIC platform:
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#define RFM70_SCK( x ) PIN_COPY( PORTC, 0, (x) )
#define RFM70_MOSI( x ) PIN_COPY( PORTC, 1, (x) )
#define RFM70_MISO ( RC2 )
#define RFM70_CSN( x ) PIN_COPY( PORTC, 3, (x) )
#define RFM70_CE( x ) PIN_COPY( PORTC, 4, (x) )
#define RFM70_PIN_DIRECTION { \
TRISC0 = 0; \
TRISC1 = 0; \
TRISC2 = 1; \
TRISC3 = 0; \
TRISC4 = 0; \
}
#define RFM70_WAIT_US( x ) WAIT_US( x )
#define RFM70_WAIT_MS( x ) wait_ms( x )
rfm73-config.h
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// standard SPI pins not available on wt32, need to use non standard pins
#define PIN_RFM73_CE GPIO_NUM_5
#define PIN_RFM73_CSN GPIO_NUM_17
#define PIN_RFM73_MISO GPIO_NUM_2
#define PIN_RFM73_MOSI GPIO_NUM_15
#define PIN_RFM73_SCK GPIO_NUM_14
#define RFM73_CE(pin_state) gpio_set_level(PIN_RFM73_CE, pin_state)
#define RFM73_CSN(pin_state) gpio_set_level(PIN_RFM73_CSN, pin_state)
#define RFM73_MISO gpio_get_level(PIN_RFM73_MISO)
#define RFM73_MOSI(pin_state) gpio_set_level(PIN_RFM73_MOSI, pin_state)
#define RFM73_PIN_DIRECTION rfm73_config_init()
#define RFM73_SCK(pin_state) gpio_set_level(PIN_RFM73_SCK, pin_state)
#define RFM73_WAIT_MS(period_millis) vTaskDelay(period_millis/portTICK_PERIOD_MS)
#define RFM73_WAIT_US(period_micros) vTaskDelay((period_micros*1000) / portTICK_PERIOD_MS)
void rfm73_config_init();
void rfm73_config_init_gpio(gpio_mode_t mode, uint64_t bit_mask, gpio_pulldown_t pulldown, gpio_pulldown_t pullup);
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#include <rfm73-config.h>
void rfm73_config_init(){
rfm73_config_init_gpio(GPIO_MODE_INPUT, (1ULL<<PIN_RFM73_MISO), 0, 0);
rfm73_config_init_gpio(GPIO_MODE_OUTPUT, ((1ULL<<PIN_RFM73_MOSI) | (1ULL<<PIN_RFM73_SCK)), 0, 0);
rfm73_config_init_gpio(GPIO_MODE_OUTPUT, ((1ULL<<PIN_RFM73_CE) | (1ULL<<PIN_RFM73_CSN)), 0, 1);
}
void rfm73_config_init_gpio(gpio_mode_t mode, uint64_t bit_mask, gpio_pulldown_t pulldown, gpio_pulldown_t pullup){
gpio_config_t gpio_config_1={};
gpio_config_1.intr_type = GPIO_INTR_DISABLE;
gpio_config_1.mode = mode;
gpio_config_1.pin_bit_mask = bit_mask;
gpio_config_1.pull_down_en = pulldown;
gpio_config_1.pull_up_en = pullup;
//configure GPIO with the given settings
ESP_ERROR_CHECK(gpio_config(&gpio_config_1));
}
My code fails and the rfm73.c code hangs when calling this method:
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void rfm73_register_write( unsigned char reg, unsigned char value ){
if( reg < RFM73_CMD_WRITE_REG ){
reg |= RFM73_CMD_WRITE_REG;
}
RFM73_CSN( 0 ); // CSN low, init SPI transaction
(void)rfm73_SPI_RW( reg ); // select register
(void)rfm73_SPI_RW( value ); // ..and write value to it..
RFM73_CSN( 1 ); // CSN high again
}
Isn't the SCK pin meant to output a clock signal, nowhere do I see that.
Instead the SCK pin is either set high or low.
Can anyone suggest what my rfm73-config.h should contain for my WT32-ETH01?
Can I use the ESP-IDF SPI Master Driver instead of bitbanging?
Thanks for any and all help on this one!