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Diffstat (limited to 'src/devices/video/pwm.cpp')
-rw-r--r--src/devices/video/pwm.cpp125
1 files changed, 57 insertions, 68 deletions
diff --git a/src/devices/video/pwm.cpp b/src/devices/video/pwm.cpp
index b5a4827e5f0..0a506597a08 100644
--- a/src/devices/video/pwm.cpp
+++ b/src/devices/video/pwm.cpp
@@ -2,28 +2,28 @@
// copyright-holders:hap
/*
-This thing is a generic helper for PWM(strobed) display elements, to prevent flickering
-and optionally handle perceived brightness levels.
+This thing is a generic helper for PWM(strobed) display elements, to prevent
+flickering and optionally handle perceived brightness levels.
-Common usecase is to call matrix(selmask, datamask), a collision between the 2 masks
-implies a powered-on display element (eg. a LED, or VFD sprite). The maximum matrix
-size is 64 by 64, simply due to uint64_t constraints. If a larger size is needed,
-create an array of pwm_display_device.
+Common usecase is to call matrix(selmask, datamask), a collision between the
+2 masks implies a powered-on display element (eg. a LED, or VFD sprite).
+The maximum matrix size is 64 by 64, simply due to uint64_t constraints.
+If a larger size is needed, create an array of pwm_display_device.
-If display elements are directly addressable, you can also use write_element or write_row
-to set them. In this case it is required to call update() to apply the changes.
+If display elements are directly addressable, you can also use write_element
+or write_row to set them.
-Display element states are sent to output tags "y.x" where y is the matrix row number,
-x is the row bit. It is also sent to "y.a" for all rows. The output state is 0 for off,
-and >0 for on, depending on brightness level. If segmask is defined, it is also sent
-to "digity", for use with multi-state elements, eg. 7seg leds.
+Display element states are sent to output tags "y.x" where y is the matrix row
+number, x is the row bit. It is also sent to "y.a" for all rows. The output state
+is 0 for off, and >0 for on, depending on brightness level. If segmask is defined,
+it is also sent to "digity", for use with multi-state elements, eg. 7seg leds.
-If you use this device in a slot, or use multiple of them (or just don't want to use
-the default output tags), set a callback.
+If you use this device in a slot, or use multiple of them (or just don't want
+to use the default output tags), set a callback.
-Brightness tresholds (0.0 to 1.0) indicate how long an element was powered on in the last
-frame, eg. 0.01 means a minimum on-time for 1%. Some games use two levels of brightness
-by strobing elements longer.
+Brightness tresholds (0.0 to 1.0) indicate how long an element was powered on
+in the last frame, eg. 0.01 means a minimum on-time for 1%. Some games use two
+levels of brightness by strobing elements longer.
TODO:
@@ -43,7 +43,7 @@ DEFINE_DEVICE_TYPE(PWM_DISPLAY, pwm_display_device, "pwm_display", "PWM Display"
// constructor
//-------------------------------------------------
-pwm_display_device::pwm_display_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+pwm_display_device::pwm_display_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock) :
device_t(mconfig, PWM_DISPLAY, tag, owner, clock),
m_out_x(*this, "%u.%u", 0U, 0U),
m_out_a(*this, "%u.a", 0U),
@@ -63,7 +63,6 @@ pwm_display_device::pwm_display_device(const machine_config &mconfig, const char
}
-
//-------------------------------------------------
// device_start/reset
//-------------------------------------------------
@@ -84,16 +83,14 @@ void pwm_display_device::device_start()
}
// initialize
+ m_rowsel = 0;
std::fill(std::begin(m_rowdata), std::end(m_rowdata), 0);
- std::fill(std::begin(m_rowdata_prev), std::end(m_rowdata_prev), 0);
+
for (auto &bri : m_bri)
std::fill(std::begin(bri), std::end(bri), 0.0);
m_frame_timer = machine().scheduler().timer_alloc(timer_expired_delegate(FUNC(pwm_display_device::frame_tick),this));
- m_update_time = machine().time();
-
- m_rowsel = 0;
- m_rowsel_prev = 0;
+ m_sync_time = machine().time();
// register for savestates
save_item(NAME(m_width));
@@ -107,12 +104,10 @@ void pwm_display_device::device_start()
save_item(NAME(m_segmask));
save_item(NAME(m_rowsel));
- save_item(NAME(m_rowsel_prev));
save_item(NAME(m_rowdata));
- save_item(NAME(m_rowdata_prev));
save_item(NAME(m_bri));
- save_item(NAME(m_update_time));
+ save_item(NAME(m_sync_time));
save_item(NAME(m_acc));
}
@@ -122,11 +117,10 @@ void pwm_display_device::device_reset()
fatalerror("%s: Invalid size %d*%d, maximum is 64*64!\n", tag(), m_height, m_width);
schedule_frame();
- m_update_time = machine().time();
+ m_sync_time = machine().time();
}
-
//-------------------------------------------------
// public handlers (most of the interface is in the .h file)
//-------------------------------------------------
@@ -156,8 +150,10 @@ pwm_display_device &pwm_display_device::set_segmask(u64 digits, u64 mask)
return *this;
}
-void pwm_display_device::matrix_partial(u8 start, u8 height, u64 rowsel, u64 rowdata, bool upd)
+void pwm_display_device::matrix_partial(u8 start, u8 height, u64 rowsel, u64 rowdata)
{
+ sync();
+
u64 selmask = (u64(1) << height) - 1;
rowsel &= selmask;
selmask <<= start;
@@ -170,45 +166,8 @@ void pwm_display_device::matrix_partial(u8 start, u8 height, u64 rowsel, u64 row
m_rowdata[y] = (rowsel & 1) ? (rowdata & rowmask) : 0;
rowsel >>= 1;
}
-
- if (upd)
- update();
}
-void pwm_display_device::update()
-{
- // call this every time after m_rowdata is changed (automatic with matrix)
- const attotime now = machine().time();
- const attotime diff = (m_update_time >= now) ? attotime::zero : now - m_update_time;
-
- u64 sel = m_rowsel_prev;
- m_rowsel_prev = m_rowsel;
-
- // accumulate active time
- for (int y = 0; y < m_height; y++)
- {
- u64 row = m_rowdata_prev[y];
- m_rowdata_prev[y] = m_rowdata[y];
-
- if (diff != attotime::zero)
- {
- if (sel & 1)
- m_acc[y][m_width] += diff;
-
- for (int x = 0; x < m_width; x++)
- {
- if (row & 1)
- m_acc[y][x] += diff;
- row >>= 1;
- }
- }
- sel >>= 1;
- }
-
- m_update_time = now;
-}
-
-
//-------------------------------------------------
// internal handlers
@@ -239,7 +198,7 @@ TIMER_CALLBACK_MEMBER(pwm_display_device::frame_tick)
if (cutoff > 1.0)
cutoff = 1.0;
- update(); // final timeslice
+ sync(); // final timeslice
for (int y = 0; y < m_height; y++)
{
@@ -290,3 +249,33 @@ TIMER_CALLBACK_MEMBER(pwm_display_device::frame_tick)
schedule_frame();
}
+
+void pwm_display_device::sync()
+{
+ const attotime now = machine().time();
+ const attotime last = m_sync_time;
+ m_sync_time = now;
+
+ if (last >= now)
+ return;
+
+ const attotime diff = now - last;
+ u64 sel = m_rowsel;
+
+ // accumulate active time
+ for (int y = 0; y < m_height; y++)
+ {
+ u64 row = m_rowdata[y];
+
+ if (sel & 1)
+ m_acc[y][m_width] += diff;
+
+ for (int x = 0; x < m_width; x++)
+ {
+ if (row & 1)
+ m_acc[y][x] += diff;
+ row >>= 1;
+ }
+ sel >>= 1;
+ }
+}