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;************************************************************************************
;*   File:     tamagawa_send.h											            *
;*																					*
;*   Brief:    Macro for sending commands to the Tamagawa encoder				    *
;************************************************************************************

;*************************************************************************************************************************************
;   Macro: TAMAGAWA_SEND_MACRO
;
;   		Send the Tx data for non-EEPROM commands to the Tamagawa encoders.
;
;	Registers:
;						R27.b0- Stores the first byte of the TX data
;						R27.b1- Stores the second byte of the TX data
;						R30.b0- Used to load Tx FIFO for a selected channel
;                       R30.b2- Used to select the channel (R30[17:16])
;
;
;
;   PseudoCode:
;      (start code)
;		1.Load the Tx FIFO with the first byte for the currently selected channel by writing to the R30.b0.
;       2.Load the Tx FIFO with the second byte for the currently selected channel by writing to the R30.b0.
;		3.Loop through the steps 1-4 thrice in case of multi-channel configuration to fill Tx FIFO for all selected channels.
;		4.Once the Tx FIFO of all the selected channels is loaded with 2 bytes, make a call to the FN_SEND function that performs Tx in single shot mode with Tx frame size = 10 bits.
;		(end code)
;
;   Parameters:
;       tx_data0 - Stores the first byte of the tx data to be sent to the encoder
;       tx_data1 - Stores the second byte of the tx data to be sent to the encoder
;
;   Worst case peak cycle usage:   68 (approx.)
;   For all commands except EEPROM Read and Write, the Control Field (CF) should be transmitted to the encoder in about 2.0 +/- 0.05 μs and 4.0 +/- 0.1 μs for 5 Mbps and 2.5 Mbps Tamagawa encoders respectively.
;
;**************************************************************************************************************************************

	.if	!$isdefed("__tamagawa_send_h")
__tamagawa_send_h	.set	1

	.include "tamagawa_interface.h"
    .include "tamagawa_constants.h"
    .global FN_SEND
    .global CALL
    .global CALL2

TAMAGAWA_SEND_MACRO   .macro     tx_data0, tx_data1
    .if	$defined("ENABLE_MULTI_CHANNEL")
    ;In each iteration, channel is selected and Tx Fifo is loaded .
    LOOP	SEND_RECEIVE_TAMAGAWA_MULTI_CHANNEL?,	3
	.endif
    ;In case of non EEPROM commands, we need to send the control field to the encoder. This control field is of 10 bits.
    ;The FIFO is loaded with 16 bits first and then a call to the FN_SEND is made in order to start Tx in Single shot mode with Tx frame size = 10 bits.
    ;load Tx FIFO
    MOV R30.b0,tx_data0
    ;load Tx FIFO
    MOV R30.b0,tx_data1

    .if	$defined("ENABLE_MULTI_CHANNEL")
    ;	 last channel would have been selected first
    ;R30[17:16] tx_ch_sel is decremented to select next channel and load Tx Fifo.
    SUB		R30.b2,	R30.b2,	1
SEND_RECEIVE_TAMAGAWA_MULTI_CHANNEL?:
	.endif
    ;	Sending Tx Fifo data via Data line(PERIF0_OUT,PERIF1_OUT,PERIF2_OUT) to encoders
    CALL2		FN_SEND

	.endm

	.endif