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author | Vas Crabb <vas@vastheman.com> | 2018-07-07 02:40:29 +1000 |
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committer | Vas Crabb <vas@vastheman.com> | 2018-07-07 02:40:29 +1000 |
commit | c3fb11c2c98a5c28ece6a27093a0f9def350ac64 (patch) | |
tree | c68b38f05ed1d32358add721fda7f45e8803479f /src/mame/drivers/apricot.cpp | |
parent | 5d9e33b786d7ef452317439359f3cbd8cc920513 (diff) |
devcb3
There are multiple issues with the current device callbacks:
* They always dispatch through a pointer-to-member
* Chained callbacks are a linked list so the branch unit can't predict the early
* There's a runtime decision made on the left/right shift direction
* There are runtime NULL checks on various objects
* Binding a lambda isn't practical
* Arbitrary transformations are not supported
* When chaining callbacks it isn't clear what the MCFG_DEVCB_ modifiers apply to
* It isn't possible to just append to a callback in derived configuration
* The macros need a magic, hidden local called devcb
* Moving code that uses the magic locals around is error-prone
* Writing the MCFG_ macros to make a device usable is a pain
* You can't discover applicable MCFG_ macros with intellisense
* Macros are not scoped
* Using an inappropriate macro isn't detected at compile time
* Lots of other things
This changeset overcomes the biggest obstacle to remving MCFG_ macros
altogether. Essentially, to allow a devcb to be configured, call
.bind() and expose the result (a bind target for the callback). Bind
target methods starting with "set" repace the current callbacks; methods
starting with "append" append to them. You can't reconfigure a callback
after resolving it. There's no need to use a macro matching the
handler signatures - use FUNC for everything. Current device is implied
if no tag/finder is supplied (no need for explicit this).
Lambdas are supported, and the memory space and offset are optional.
These kinds of things work:
* .read_cb().set([this] () { return something; });
* .read_cb().set([this] (offs_t offset) { return ~offset; });
* .write_cb().set([this] (offs_t offset, u8 data) { m_array[offset] = data; });
* .write_cb().set([this] (int state) { some_var = state; });
Arbitrary transforms are allowed, and they can modify offset/mask for example:
* .read_cb().set(FUNC(my_state::handler)).transform([] (u8 data) { return bitswap<4>(data, 1, 3, 0, 2); });
* .read_cb().set(m_dev, FUNC(some_device::member)).transform([] (offs_t &offset, u8 data) { offset ^= 3; return data; });
It's possible to stack arbitrary transforms, at the cost of compile
time (the whole transform stack gets inlined at compile time). Shifts
count as an arbitrary transform, but mask/exor does not.
Order of mask/shift/exor now matters. Modifications are applied in the
specified order. These are NOT EQUIVALENT:
* .read_cb().set(FUNC(my_state::handler)).mask(0x06).lshift(2);
* .read_cb().set(FUNC(my_state::handler)).lshift(2).mask(0x06);
The bit helper no longer reverses its behaviour for read callbacks, and
I/O ports are no longer aware of the field mask. Binding a read
callback to no-op is not supported - specify a constant. The GND and
VCC aliases have been removed intentionally - they're TTL-centric, and
were already being abused.
Other quirks have been preserved, including write logger only logging
when the data is non-zero (quite unhelpful in many of the cases where
it's used). Legacy syntax is still supported for simple cases, but will
be phased out. New devices should not have MCFG_ macros.
I don't think I've missed any fundamental issues, but if I've broken
something, let me know.
Diffstat (limited to 'src/mame/drivers/apricot.cpp')
-rw-r--r-- | src/mame/drivers/apricot.cpp | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/src/mame/drivers/apricot.cpp b/src/mame/drivers/apricot.cpp index 736f9726a59..d6e03a92627 100644 --- a/src/mame/drivers/apricot.cpp +++ b/src/mame/drivers/apricot.cpp @@ -408,15 +408,15 @@ MACHINE_CONFIG_START(apricot_state::apricot) MCFG_DEVICE_ADD("ic31", PIC8259, 0) MCFG_PIC8259_OUT_INT_CB(INPUTLINE("ic91", 0)) - MCFG_DEVICE_ADD("ic16", PIT8253, 0) - MCFG_PIT8253_CLK0(4_MHz_XTAL / 16) - MCFG_PIT8253_OUT0_HANDLER(WRITELINE("ic31", pic8259_device, ir6_w)) - MCFG_PIT8253_CLK1(4_MHz_XTAL / 2) - MCFG_PIT8253_OUT1_HANDLER(WRITELINE("ic14", ttl153_device, i0a_w)) - MCFG_PIT8253_CLK2(4_MHz_XTAL / 2) - MCFG_PIT8253_OUT2_HANDLER(WRITELINE("ic14", ttl153_device, i0b_w)) - MCFG_DEVCB_CHAIN_OUTPUT(WRITELINE("ic14", ttl153_device, i2a_w)) - MCFG_DEVCB_CHAIN_OUTPUT(WRITELINE("ic14", ttl153_device, i2b_w)) + PIT8253(config, m_pit, 0); + m_pit->set_clk<0>(4_MHz_XTAL / 16); + m_pit->out_handler<0>().set("ic31", FUNC(pic8259_device::ir6_w)); + m_pit->set_clk<1>(4_MHz_XTAL / 2); + m_pit->out_handler<1>().set("ic14", FUNC(ttl153_device::i0a_w)); + m_pit->set_clk<2>(4_MHz_XTAL / 2); + m_pit->out_handler<2>().set("ic14", FUNC(ttl153_device::i0b_w)); + m_pit->out_handler<2>().append("ic14", FUNC(ttl153_device::i2a_w)); + m_pit->out_handler<2>().append("ic14", FUNC(ttl153_device::i2b_w)); MCFG_DEVICE_ADD("ic14", TTL153) MCFG_TTL153_ZA_CB(WRITELINE("ic15", z80sio_device, rxca_w)) @@ -437,12 +437,12 @@ MACHINE_CONFIG_START(apricot_state::apricot) MCFG_Z80SIO_OUT_INT_CB(WRITELINE("ic31", pic8259_device, ir5_w)) // rs232 port - MCFG_DEVICE_ADD("rs232", RS232_PORT, default_rs232_devices, nullptr) + RS232_PORT(config, m_rs232, default_rs232_devices, nullptr); // note: missing a receive clock callback to support external clock mode (i1 to 153) - MCFG_RS232_RXD_HANDLER(WRITELINE("ic15", z80sio_device, rxa_w)) - MCFG_RS232_DCD_HANDLER(WRITELINE("ic15", z80sio_device, dcda_w)) - MCFG_RS232_DSR_HANDLER(WRITELINE("ic15", z80sio_device, synca_w)) - MCFG_RS232_CTS_HANDLER(WRITELINE("ic15", z80sio_device, ctsa_w)) MCFG_DEVCB_XOR(1) + m_rs232->rxd_handler().set(m_sio, FUNC(z80sio_device::rxa_w)); + m_rs232->dcd_handler().set(m_sio, FUNC(z80sio_device::dcda_w)); + m_rs232->dsr_handler().set(m_sio, FUNC(z80sio_device::synca_w)); + m_rs232->cts_handler().set(m_sio, FUNC(z80sio_device::ctsa_w)).invert(); // keyboard MCFG_APRICOT_KEYBOARD_INTERFACE_ADD("kbd", "hle") |