HD64F3028F25 Datasheet, PDF (305/925 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

8.9 Port 8
8.9.1 Overview
Port 8 is a 5-bit input/output port that is also used for CS₃ to CS₀ output, RFSH output, IRQ₃ to
IRQ₀ input, and A/D converter ADTRG input. Figure 8.8 shows the pin configuration of port 8.
In modes 1 to 5 (expanded modes), port 8 can provide CS₃ to CS₀ output, RFSH output, IRQ₃ to
IRQ₀ input, and ADTRG input. See table 8.14 for the selection of pin functions in expanded
modes.
In modes 6 and 7 (single-chip modes), port 8 can provide IRQ₃ to IRQ₀ input and ADTRG input.
See table 8.15 for the selection of pin functions in single-chip mode.
See section 15, A/D Converter, for a description of the A/D converter's ADTRG input pin.
The IRQ₃ to IRQ₀ functions are selected by IER settings, regardless of whether the pin is used for
input or output. Caution is therefore required. For details see section 5.3.1, External Interrupts.
When DRAM is connected to areas 2 to 5, the CS₃ and CS₂ output pins function as RAS output
pins for each area. For details see section 6.5, DRAM Interface.
Pins in port 8 can drive one TTL load and a 90-pF capacitive load. They can also drive a
darlington transistor pair.
Pins P8₂ to P8₀ have Schmitt-trigger inputs.
Rev. 2.00, 09/03, page 273 of 890