19.11.19 Input Capture Register 4 Low and High byte
The ICR4L and ICR4H register pair represents the 16-bit value, ICR4. The low byte [7:0] (suffix L) is accessible at the original offset. The high byte [15:8] (suffix H) can be accessed at offset + 0x01. For more details on reading and writing 16-bit registers, refer to Accessing 16-bit Timer/Counter Registers.
| Name: | ICR4L and ICR4H |
| Offset: | 0xA6 |
| Reset: | 0x00 |
| Property: | - |
| Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
| ICR4[15:8] | |||||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| ICR4[7:0] | |||||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | R/W | |
| Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
Bits 15:0 – ICR4[15:0] Input Capture 3
The Input Capture is updated with the counter (TCNT4) value each time an event occurs on the ICP4 pin (or optionally on the Analog Comparator output for Timer/Counter4). The Input Capture can be used for defining the counter TOP value.
The Input Capture Register is 16-bit in size. To ensure that both the high and low bytes are read simultaneously when the CPU accesses these registers, the access is performed using an 8-bit temporary High Byte Register (TEMP). This temporary register is shared by all the other 16-bit registers. Refer to Accessing 16-bit Timer/Counter Registers for details.