Need SPI documentation about punyforth HOT 4 OPEN

On Mon, Sep 11, 2017 at 10:20 AM, Attila Magyar ***@***.***> wrote: The spi functions are based on There is a thin wrapper: https://github.com/zeroflag/punyforth/blob/feab7a0fea1c815a5dc441085251fd ea44c7089e/arch/esp8266/rtos/user/forth_spi.c And the Forth words are here: https://github.com/zeroflag/punyforth/blob/6a2e89c1969c12798d627f9b5c4932 6139f99e8a/arch/esp8266/ext.S#L394 There isn't any user friendly documentation yet, but you can check the stack usage. For example spi-send8 is defined as follows: defprimitive "spi-send8",9,spi_send8,REGULAR DPOP a2 // bus DPOP a3 // data CCALL forth_spi_send8 DPUSH a2 NEXT So the stack effect should be : spi-send8 ( data bus -- result ) I think you're right saying that the read should be implemented by using the send. But I didn't need to use read so far. There are some examples of using spi-init and send in https://github.com/zeroflag/punyforth/blob/master/arch/ esp8266/forth/ssd1306-spi.forth — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#31 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AEM6-LZo3e2p0hAsTE_lclwjO0D2HCvpks5shV21gaJpZM4PTZiI> .

On Mon, Sep 11, 2017 at 11:17 AM, Attila Magyar ***@***.***> wrote: Here is the documentation of spi_transfer from https://github.com/SuperHouse/esp-open-rtos/blob/ 61c3d509e5b930c6c1b269ceff99e2d1f60d2010/core/include/esp/spi.h#L275 * \param bus Bus ID: 0 - system, 1 - user * \param out_data Data to send. * \param in_data Receive buffer. If NULL, received data will be lost. * \param len Buffer size in words * \param word_size Size of the word * \return Transmitted/received words count */ size_t spi_transfer(uint8_t bus, const void *out_data, void *in_data, size_t len, spi_word_size_t word_size); So the out_data buffer contains the data to be sent and the other one is the receive buffer. I didn't need the receive buffer when I used this (I just passed 0) so I don't have more information on this beside what's in the C comment. This may help regarding the spi-get-freq-div constant. /** * Macro for use with spi_init and spi_set_frequency_div. * SPI frequency = 80000000 / divider / count * dvider must be in 1..8192 and count in 1..64 */ #define SPI_GET_FREQ_DIV(divider, count) (((count) << 16) | ((divider) & 0xffff)) /** * Predefinded SPI frequency dividers */ #define SPI_FREQ_DIV_125K SPI_GET_FREQ_DIV(64, 10) ///< 125kHz #define SPI_FREQ_DIV_250K SPI_GET_FREQ_DIV(32, 10) ///< 250kHz #define SPI_FREQ_DIV_500K SPI_GET_FREQ_DIV(16, 10) ///< 500kHz #define SPI_FREQ_DIV_1M SPI_GET_FREQ_DIV(8, 10) ///< 1MHz #define SPI_FREQ_DIV_2M SPI_GET_FREQ_DIV(4, 10) ///< 2MHz #define SPI_FREQ_DIV_4M SPI_GET_FREQ_DIV(2, 10) ///< 4MHz #define SPI_FREQ_DIV_8M SPI_GET_FREQ_DIV(5, 2) ///< 8MHz #define SPI_FREQ_DIV_10M SPI_GET_FREQ_DIV(4, 2) ///< 10MHz #define SPI_FREQ_DIV_20M SPI_GET_FREQ_DIV(2, 2) ///< 20MHz #define SPI_FREQ_DIV_40M SPI_GET_FREQ_DIV(1, 2) ///< 40MHz #define SPI_FREQ_DIV_80M SPI_GET_FREQ_DIV(1, 1) ///< 80MHz — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#31 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AEM6-Od7_Jp_T1YjFV3_B5TYeGaXGG-hks5shWrzgaJpZM4PTZiI> .