8.3.11.3 Typical Application of the Temperature Monitor
In a typical application the temperature monitor and interrupts are used in the following manner:
- After the WAKEUP pin has been pulled high, the Application Processor (AP) writes 0x80h to the TMST1 register (address 0x0Dh). This starts the temperature measurement.
- The AP waits for the EOC interrupt. Alternatively the AP can poll the CONV_END bit in register TMST1. This will notify the AP that the A/D conversion is complete and the new temperature reading is available in the TMST_VALUE register (address (0x00h).
- The AP reads the temperature value from the TMST_VALUE register (address (0x00h).
- If the temperature changes by ±2°C (default) or more from the first reading, the processor is notified by the DTX interrupt. The A/P may or may not decide to select a different set of wave forms to drive the panel.
- If the temperature is outside the allowed operating range of the panel, the processor is notified by the THOT and TCOLD interrupts, respectively. It may or may not decide to continue with the page update.
- Once an overtemperature or undertemperature has been detected, the AP must reset the TMST_HOT_EN or TMST_COLD_EN bits, respectively, to avoid the nINT pin to be continuously pulled low. The TMST_HOT and TMST_COLD interrupt bits then must be polled continuously, to determine when the panel temperature recovers to the normal operating range. Once the temperature has recovered, the TMST_HOT_EN or TMST_COLD_EN bits must be set to 1 again and normal operation can resume.