RE: Programming an LCD with nRF51 using SPI

Hung Bui — Tue, 28 Jun 2016 12:27:13 GMT

@LK: Please don't attach the long source code, it's not possible to read anyway. Please remove them and add a file instead. I still don't know what is the issue ? Have you tried to request the library or example code from the LCD manufacturer ?

RE: Programming an LCD with nRF51 using SPI

LK13131 — Tue, 28 Jun 2016 12:09:53 GMT

Hi Hung Bui,

Yes, I have explored the spi_master example and I have tried to complete the following 5 steps for establishing an SPI connection to the LCD screen, which I found on another posted question on this forum:

devzone.nordicsemi.com/.../

Control the SS pin manually by configuring it as a GPIO output and and setting it high initially.
Break your data into 255 byte chunks Before sending data set SS low.
Call nrf_drv_spi_transfer() for first chunk
Wait for SPI event handler to know when transfer is complete
Repeat 4-5 until all data is transferred, then set SS high.

To follow these steps, I added the following code to main(): (data is random data for an 'image')

//Control the SS pin manually by configuring it as a GPIO output and and setting it high initially.
nrf_gpio_cfg_output(SPI_SS);
nrf_drv_gpiote_out_set(SPI_SS);

//Break your data into 255 byte chunks
data = {{0x9E, 0xCA, 0xDC, 0x24, 0x0E, 0xE5, 0xA9, 0xE0, 0x93, 0xF3, 0xA3, 0xB5}};

//Before sending data set SS low
nrf_drv_gpiote_out_clear(SPI_SS);	

//Call nrf_drv_spi_transfer() for first chunk
nrf_drv_spi_transfer(p_instance, p_tx_buffer, TX_RX_MSG_LENGTH, p_rx_buffer, TX_RX_MSG_LENGTH);

//Wait for SPI event handler to know when transfer is complete

//Repeat 4-5 until all data is transferred, then set SS high.
nrf_drv_gpiote_out_set(SPI_SS);

RE: Programming an LCD with nRF51 using SPI

Hung Bui — Tue, 28 Jun 2016 11:54:47 GMT

@LK13131: Have you tried to play with our SPI example and the spi driver in our SDK ?