Describe the following addressing modes: direct, page zero, register. Describe DMA method of data transfer. Determine N for a 1ms delay in an 8085 microprocessor program.

The clock frequency is $f = 3\, \text{MHz} = 3 \times 10^6\, \text{Hz}$.
The time period of one T-state ($T_{T-state}$) is the reciprocal of the clock frequency.

$$T_{T-state} = \frac{1}{f} = \frac{1}{3 \times 10^6}\, \text{s}$$

The delay loop consists of the instructions from AGAIN: to JNZ AGAIN.

• ADD C: 4 T-states
• DCR C: 4 T