Peripheral Interface: Difference between revisions
PI_BB_GPIO: Fix LED Control description and add some details
(PI_BB_NAND_CTRL: Error bits) |
(PI_BB_GPIO: Fix LED Control description and add some details) |
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| 4 | Power Mask | Enables the power control bit line. If left off, changes to Power Control will do nothing.
| 3-2 | RTC Control | RTC communication happens through these bits. Precise meaning not fully understood.
| 1 | LED Control | If
| 0 | Power Control | If 1, the power will remain on. If 0, the device will power off.
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'''Extra Details:'''
: Whenever a GPIO control bit (with its corresponding mask bit set) is set to 1, the corresponding bit line will be set to logic high (3.3v). If set to 0 (with mask set) the bit line is set to logic low (0v).
: The LED lights up when the LED GPIO is 0 as the LED requires a voltage difference across it to light up. One side of the LED is fixed to 3.3v while the other side is connected to the LED GPIO port; when LED Control is 1 there is no voltage difference across the LED (3.3 - 3.3 = 0v) so it does not light up, while an LED Control of 0 creates a voltage difference (3.3 - 0 = 3.3v) so the LED lights up.
==== <span style="display:none;">0x0460 0070 - PI_BB_NAND_ADDR</code> ====
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