18.11.20 Output Compare Register 4 A Low and High byte
The OCR4AL and OCR4AH register pair represents the 16-bit value, OCR4A.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 Registers.
| Name: | OCR4AL and OCR4AH |
| Offset: | 0xA8 |
| Reset: | 0x00 |
| Property: | - |
| Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
| OCR4A[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 | |
| OCR4A[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 – OCR4A[15:0] Output Compare 4 A
The Output Compare Registers contain a 16-bit value that is continuously compared with the counter value (TCNT4). A match can be used to generate an Output Compare interrupt, or to generate a waveform output on the OC4A pin.
The Output Compare Registers are 16-bit in size. To ensure that both the high and low bytes are written simultaneously when the CPU writes to 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.