Datasheet
2. Enable the clock to the appropriate GPIO port that is used for the 1-Wire signals using the
General-Purpose Input/Output Run Mode Clock gating Control (RCGCGPIO) in the System
Control Module; see page 398. To find out which GPIO port to enable, refer to Table
31-5 on page 2087.
3. In the GPIO module, enable the appropriate pin for its alternate function using the GPIO Alternate
Function Select (GPIOAFSEL) register (see page 801).
4. Configure the PMCn fields in the GPIOPCTL register to assign the 1-Wire signals to the
appropriate pins. See page 818 and Table 31-5 on page 2087.
5. Optionally enable interrupts to be notified when the transactions completes.
6. Write to the ONEWIREDATW register with the data to write (1, 2, 3, or 4 bytes).
7. Write to the ONEWIRECS register to set the RST bit and configure the OP (operation) and SZ
fields. When configuring all three bit fields, the reset is performed first, followed by the operation
(unless an error occurs) and then any interrupt triggers.
8. If normal interrupts are generated (for example, OPC and RST), clear these interrupts and read
the ONEWIREDATR register if a read or read/write transaction occurred.
9. If the 1-Wire master has more data to write and/or read for the same command, repeat the
previous two steps but without setting the RST bit. If a new command is required, repeat the
previous two steps including the reset enable.
22.5 Register Map
Table 22-4 on page 1515 lists the 1-Wire Master Module registers. The offset listed is a hexadecimal
increment to the register's address, relative to the 1-Wire Master module's base address
0x400B.6000.
Table 22-4. OWIRE Register Map
See
page
DescriptionResetTypeNameOffset
15171-Wire Control and Status0x0000.0000RWONEWIRECS0x000
15211-Wire Timing Override0x0000.0000RWONEWIRETIM0x004
15221-Wire Data Write0x0000.0000RWONEWIREDATW0x008
15231-Wire Data Read0x0000.0000RWONEWIREDATR0x00C
15241-Wire Interrupt Mask0x0000.0000RWONEWIREIM0x100
15261-Wire Raw Interrupt Status0x0000.0000ROONEWIRERIS0x104
15281-Wire Masked Interrupt Status0x0000.0000ROONEWIREMIS0x108
15301-Wire Interrupt Clear0x0000.0000RW1CONEWIREICR0x10C
15311-Wire µDMA Control0x0000.0000RWONEWIREDMA0x120
15331-Wire Peripheral Properties0x0000.0011ROONEWIREPP0xFC0
1515December 13, 2013
Texas Instruments-Advance Information
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TM4C129XNCZAD Microcontroller