gt911_emu.c File Reference

The GT911 register file as an I2C target sees it (gt911_emu.h). More...

#include "gt911_emu.h"
#include <string.h>

Functions
void	gt911_emu_init (gt911_emu_t *e, uint16_t res_x, uint16_t res_y)
	Clear the register file and set the resolution it reports.
static uint8_t	lo (uint16_t v)
	The low byte of v.
static uint8_t	hi (uint16_t v)
	The high byte of v.
uint8_t	gt911_emu_peek (const gt911_emu_t *e, uint16_t reg)
	The byte at reg, as a read would return it, without side effects.
void	gt911_emu_rx (gt911_emu_t *e, uint8_t b)
	The master wrote b.
uint8_t	gt911_emu_tx (gt911_emu_t *e)
	The master reads a byte: the one at the pointer, which then moves on.
void	gt911_emu_finish (gt911_emu_t *e)
	A STOP, a repeated START or an abort ended the transfer.
bool	gt911_emu_publish (gt911_emu_t *e, const gt911_emu_frame_t *f)
	Make f the frame the master reads next.
bool	gt911_emu_withdraw (gt911_emu_t *e)
	Withdraw an unacknowledged frame: the status reads 0x00.

Detailed Description

The GT911 register file as an I2C target sees it (gt911_emu.h).

SPDX-License-Identifier: MIT

Function Documentation

gt911_emu_finish()

void gt911_emu_finish

(

gt911_emu_t *

e

)

A STOP, a repeated START or an abort ended the transfer.

Parameters

e	The emulator.

gt911_emu_init()

void gt911_emu_init	(	gt911_emu_t *	e,
		uint16_t	res_x,
		uint16_t	res_y )

Clear the register file and set the resolution it reports.

Parameters

e	The emulator.
res_x	Columns.
res_y	Rows.

gt911_emu_peek()

uint8_t gt911_emu_peek	(	const gt911_emu_t *	e,
		uint16_t	reg )

The byte at reg, as a read would return it, without side effects.

Parameters

e	The emulator.
reg	The register.

Returns

The byte.

gt911_emu_publish()

bool gt911_emu_publish	(	gt911_emu_t *	e,
		const gt911_emu_frame_t *	f )

Make f the frame the master reads next.

Refused while a transfer is under way or the previous frame is not yet acknowledged, so a master never reads the status of one frame and the points of another. Refused too for more than GT911_EMU_POINTS points. Point slots past f->n read 0x00.

Parameters

e	The emulator.
f	The frame.

Returns

Whether it is published.

gt911_emu_rx()

void gt911_emu_rx	(	gt911_emu_t *	e,
		uint8_t	b )

The master wrote b.

Parameters

e	The emulator.
b	The byte.

gt911_emu_tx()

uint8_t gt911_emu_tx

(

gt911_emu_t *

e

)

The master reads a byte: the one at the pointer, which then moves on.

Parameters

e	The emulator.

Returns

The byte.

gt911_emu_withdraw()

bool gt911_emu_withdraw

(

gt911_emu_t *

e

)

Withdraw an unacknowledged frame: the status reads 0x00.

Parameters

e	The emulator.

Returns

False while a transfer is under way, and nothing is withdrawn.