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#ifndef _LCOM_I8254_H_
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#define _LCOM_I8254_H_
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#include <lcom/lcf.h>
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/** @defgroup i8254 i8254
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 * @{
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 *
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 * Constants for programming the i8254 Timer. Needs to be completed.
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 */
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/*IRQ's*/
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#define IRQ_TIMER 0
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#define DEFAULT_FREQ 60
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#define TIMER_FREQ 1193182 /**< @brief clock frequency for timer in PC and AT */
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#define MIN_FREQ 19
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#define TIMER0_IRQ 0 /**< @brief Timer 0 IRQ line */
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/* I/O port addresses */
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#define TIMER_0    0x40 /**< @brief Timer 0 count register */
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#define TIMER_1    0x41 /**< @brief Timer 1 count register */
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#define TIMER_2    0x42 /**< @brief Timer 2 count register */
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#define TIMER_CTRL 0x43 /**< @brief Control register */
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#define SPEAKER_CTRL 0x61 /**< @brief Register for speaker control  */
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/* Timer control */
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/* Timer selection: bits 7 and 6 */
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#define TIMER_SEL0   0x00              /**< @brief Control Word for Timer 0 */
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#define TIMER_SEL1   BIT(6)            /**< @brief Control Word for Timer 1 */
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#define TIMER_SEL2   BIT(7)            /**< @brief Control Word for Timer 2 */
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#define TIMER_RB_CMD (BIT(7) | BIT(6)) /**< @brief Read Back Command */
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/* Register selection: bits 5 and 4 */
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#define TIMER_LSB     BIT(4)                  /**< @brief Initialize Counter LSB only */
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#define TIMER_MSB     BIT(5)                  /**< @brief Initialize Counter MSB only */
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#define TIMER_LSB_MSB (TIMER_LSB | TIMER_MSB) /**< @brief Initialize LSB first and MSB afterwards */
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/* Operating mode: bits 3, 2 and 1 */
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#define TIMER_SQR_WAVE (BIT(2) | BIT(1)) /**< @brief Mode 3: square wave generator */
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#define TIMER_RATE_GEN BIT(2)            /**< @brief Mode 2: rate generator */
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/* Counting mode: bit 0 */
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#define TIMER_BCD 0x01 /**< @brief Count in BCD */
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#define TIMER_BIN 0x00 /**< @brief Count in binary */
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/* READ-BACK COMMAND FORMAT */
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#define TIMER_RB_COUNT_  BIT(5)
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#define TIMER_RB_STATUS_ BIT(4)
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#define TIMER_RB_SEL(n)  BIT((n) + 1)
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/**@}*/
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#endif /* _LCOM_I8254_H */