Datasheet MAX31889 (Maxim) - 11
| Manufacturer | Maxim |
| Description | ±0.25°C Accurate I2C Temperature Sensor |
| Pages / Page | 31 / 11 — GPIO. Table 2. GPIO Mode Functions. GPIOX_MODE[1:0] (X = 0,1). GPIO0. … |
| File Format / Size | PDF / 585 Kb |
| Document Language | English |
GPIO. Table 2. GPIO Mode Functions. GPIOX_MODE[1:0] (X = 0,1). GPIO0. GPIO1
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GPIO
The MAX31889 provides access to two GPIO pins which can be used to provide additional functionality. GPIO0 can be configured to output an interrupt while GPIO1 can be configured as an input for a temperature converison. The interrupt on GPIO0 is triggered based on selectable status bits in the INTERRUPT_ENABLE[0X01] register. By writing to one of the available bits in the INTERRUPT_ENABLE register, the flag for an interrupt is raised if GPIO0_MODE[1:0] in the GPIO_SETUP[0x20] register is set to 11. When GPIO1_MODE[7:0] in the GPIO_SETUP register is set to 11, driving the line low initiates an external temperature converison. Table 1 shows a complete list of the functions of the two GPIO Pins. The state of GPIO pins and the setting of the GPIO_SETUP[0x20] register are used to determine the last two bits of the I2C address at each I2C start condition. This use of the GPIO pins is further detailed in the I2C Slave Address section.
Table 2. GPIO Mode Functions GPIOX_MODE[1:0] (X = 0,1) GPIO0 GPIO1
00 HiZ Input HiZ Input 01 Output Output 10 (default) 1MΩ Internal Pulldown Input 1MΩ Internal Pulldown Input 11 INTB CONV 19-100693 www.maximintegrated.com Maxim Integrated | 11 Document Outline General Description Applications Benefits and Features Simplified Block Diagram Absolute Maximum Ratings Package Information μDFN Electrical Characteristics Electrical Characteristics (continued) Typical Operating Characteristics Typical Operating Characteristics (continued) Pin Configuration μDFN Pin Description Functional Diagrams Detailed Description Operation Measuring Temperature Alarm Signaling GPIO I2C I2C Slave Address I2C/SMBus Compatible Serial Interface Detailed I2C Timing Diagram Bit Transfer START and STOP Conditions Early STOP Conditions Acknowledge Bit I2C Write Data Format I2C Read Data Format FIFO Description Register Map Register Map Register Details STATUS (0x0) INTERRUPT ENABLE (0x1) FIFO WRITE POINTER (0x04) FIFO READ POINTER (0x05) FIFO OVERFLOW COUNTER (0x06) FIFO DATA COUNTER (0x07) FIFO DATA (0x08) FIFO CONFIGURATION 1 (0x09) FIFO CONFIGURATION 2 (0x0A) SYSTEM CONTROL (0x0C) ALARM HIGH MSB (0x10) ALARM HIGH LSB (0x11) ALARM LOW MSB (0x12) ALARM LOW LSB (0x13) TEMP SENSOR SETUP (0x14) GPIO SETUP (0x20) GPIO CONTROL (0x21) ROM ID 1 (0x31) ROM ID 2 (0x32) ROM ID 3 (0x33) ROM ID 4 (0x34) ROM ID 5 (0x35) ROM ID 6 (0x36) PART IDENTIFIER (0xFF) Applications Information Measurement Considerations Typical Application Circuit Ordering Information Revision History
GPIO
The MAX31889 provides access to two GPIO pins which can be used to provide additional functionality. GPIO0 can be configured to output an interrupt while GPIO1 can be configured as an input for a temperature converison. The interrupt on GPIO0 is triggered based on selectable status bits in the INTERRUPT_ENABLE[0X01] register. By writing to one of the available bits in the INTERRUPT_ENABLE register, the flag for an interrupt is raised if GPIO0_MODE[1:0] in the GPIO_SETUP[0x20] register is set to 11. When GPIO1_MODE[7:0] in the GPIO_SETUP register is set to 11, driving the line low initiates an external temperature converison. Table 1 shows a complete list of the functions of the two GPIO Pins. The state of GPIO pins and the setting of the GPIO_SETUP[0x20] register are used to determine the last two bits of the I2C address at each I2C start condition. This use of the GPIO pins is further detailed in the I2C Slave Address section.
Table 2. GPIO Mode Functions GPIOX_MODE[1:0] (X = 0,1) GPIO0 GPIO1
00 HiZ Input HiZ Input 01 Output Output 10 (default) 1MΩ Internal Pulldown Input 1MΩ Internal Pulldown Input 11 INTB CONV 19-100693 www.maximintegrated.com Maxim Integrated | 11 Document Outline General Description Applications Benefits and Features Simplified Block Diagram Absolute Maximum Ratings Package Information μDFN Electrical Characteristics Electrical Characteristics (continued) Typical Operating Characteristics Typical Operating Characteristics (continued) Pin Configuration μDFN Pin Description Functional Diagrams Detailed Description Operation Measuring Temperature Alarm Signaling GPIO I2C I2C Slave Address I2C/SMBus Compatible Serial Interface Detailed I2C Timing Diagram Bit Transfer START and STOP Conditions Early STOP Conditions Acknowledge Bit I2C Write Data Format I2C Read Data Format FIFO Description Register Map Register Map Register Details STATUS (0x0) INTERRUPT ENABLE (0x1) FIFO WRITE POINTER (0x04) FIFO READ POINTER (0x05) FIFO OVERFLOW COUNTER (0x06) FIFO DATA COUNTER (0x07) FIFO DATA (0x08) FIFO CONFIGURATION 1 (0x09) FIFO CONFIGURATION 2 (0x0A) SYSTEM CONTROL (0x0C) ALARM HIGH MSB (0x10) ALARM HIGH LSB (0x11) ALARM LOW MSB (0x12) ALARM LOW LSB (0x13) TEMP SENSOR SETUP (0x14) GPIO SETUP (0x20) GPIO CONTROL (0x21) ROM ID 1 (0x31) ROM ID 2 (0x32) ROM ID 3 (0x33) ROM ID 4 (0x34) ROM ID 5 (0x35) ROM ID 6 (0x36) PART IDENTIFIER (0xFF) Applications Information Measurement Considerations Typical Application Circuit Ordering Information Revision History
