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The Hollywood chipset includes 24 general purpose I/O lines with interrupt capability. Two full sets of registers are provided, and the Broadway only has access to one halfset. Each pin can be assigned to one This set accesses a configurable subset of the two sets of registersIO pins, which lets the Starlet control which pins only it can control, and which pins the Broadway can use tooselect.
== Pin connections ==
Configures the pin state that causes an interrupt. If a bit is set in this register, the pin causes an interrupt when high (or on the rising edge?{{check}}). A zero causes the opposite behavior.
Bits in this register indicate which pins have triggered their interrupt flags. Write one to clear a bit back to zero. The bits can only be cleared if the pin is in the idle state: if the pin state equals the value in the HW_GPIO_INTLVL register, then the corresponding bit in HW_GPIO_INTFLAG will be stuck at one until the pin state reverts or the value in HW_GPIO_INTLVL is inverted. Once the pin is idle, the bits in this register may be cleared by writing one to them.
Only the bits set in this register propagate their interrupts to the master [[Hardware/Hollywood IRQs|Hollywood GPIO interrupt]] (#11). All other pin interrupts are ignored, although the interrupt state can still be queried and cleared in [[#HW_GPIO_INTFLAG|HW_GPIO_INTFLAG]]. Note: Pins configured for Broadway access do not generate Hollywood IRQ #11. Instead, they generate Hollywood IRQ #10. In other words, the IRQ generation logic for #11 is HW_GPIO_INTMASK & HW_GPIO_INTFLAG & ~HW_GPIO_OWNER.
{{regsimple2|HW_GPIO_INMIR|addr=0x0d8000f8|bits=32|split=24|access=R/W}}This register appears to contain the input state at some point in time, possibly power-on or interrupt or something like that. Writes do not seem possible. {{check}}
This register configures which pins are can be controlled with HW_GPIO registers vs by the HW_GPIOB registers. A one bit configures the pin for control via the HW_GPIOB registers, and enables access which lets it be accessed by the Broadway. A zero bit restricts access to the HW_GPIO registers, which are Starlet-only. The HW_GPIO registers always have read access to all pins, but any writes (changes) must go through the HW_GPIOB registers if the corresponding bit is set in the HW_GPIO_OWNER register.
{{regsimple2|HW_GPIOB_INMIR|addr=0x0d8000d8|bits=32|split=24|access=R/W}}These registers operate identically to their HW_GPIO counterparts above, but they only control the pins which have their respective [[#HW_GPIO_OWNER|HW_GPIO_OWNER]] bits set to 1. They can be accessed by the Broadwayas well as the Starlet. The master interrupt feeds to the [[Hardware/Hollywood IRQs|Hollywood GPIOB interrupt]] (#10). The generation logic would be HW_GPIOB_INTFLAG & HW_GPIOB_INTMASK, with an implicit AND with HW_GPIO_OWNER since the GPIOB registers are already masked with the HW_GPIO_OWNER register. When switching owners, copying of the data is not necessary. For example, if pin 0 has certain configuration in the HW_GPIO registers, and that bit is then set in the HW_GPIO_OWNER register, those settings will immediately be visible in the HW_GPIOB registers. There is only one set of data registers, and the HW_GPIO_OWNER register just controls the access that the HW_GPIOB registers have to that data.

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