unzen_hal.h

00001 #ifndef _UNZEN_HAL_H_
00002 #define _UNZEN_HAL_H_
00003 
00004 #include "mbed.h"
00005 
00006 namespace unzen 
00007 {
00008         // Set up I2S peripheral to ready to start.
00009         // By this HAL, the I2S have to become : 
00010         // - slave mode
00011         // - clock must be ready
00012     void hal_i2s_setup(void);
00013     
00014         // configure the pins of I2S and then, wait for WS. 
00015         // This waiting is important to avoid the delay between TX and RX.
00016         // The HAL API will wait for the WS changes from left to right then return.
00017         // The procesure is : 
00018         // 1. configure WS pin as GPIO
00019         // 2. wait the WS rising edge
00020         // 3. configure all pins as I2S
00021     void hal_i2s_pin_config_and_wait_ws(void);
00022 
00023     
00024         // Start I2S transfer. Interrupt starts  
00025     void hal_i2s_start(void);
00026 
00027         // returns the IRQ ID for I2S RX interrupt 
00028     IRQn_Type hal_get_i2s_irq_id(void);
00029     
00030         // returns the IRQ ID for process IRQ. Typically, this is allocated to the reserved IRQ.
00031     IRQn_Type hal_get_process_irq_id(void);
00032     
00033         // The returned value must be compatible with CMSIS NVIC_SetPriority() API. That mean, it is integer like 0, 1, 2...
00034     unsigned int hal_get_i2s_irq_priority_level(void);
00035 
00036         // The returned value must be compatible with CMSIS NVIC_SetPriority() API. That mean, it is integer like 0, 1, 2...
00037     unsigned int hal_get_process_irq_priority_level(void);
00038 
00039  
00040         // reutun the intenger value which tells how much data have to be transfered for each
00041         // interrupt. For example, if the stereo 32bit data ( total 64 bit ) have to be sent, 
00042         // have to return 2. 
00043     unsigned int hal_data_per_sample(void);
00044 
00045         // get data from I2S RX peripheral. Where sample is one audio data. Stereo data is constructed by 2 samples.   
00046     void hal_get_i2s_rx_data( int & sample);
00047     
00048         // put data into I2S TX peripheral. Where sample is one audio data. Stereo data is constructed by 2 samples.   
00049     void hal_put_i2s_tx_data( int sample );
00050 }
00051 
00052 
00053 #endif