Virtual H8 Computer Enhanced Z80 Boards

The default H8 CPU is the I8080. The following propert may override that. The value of this property should contain a list of featues, separated by underscore characters.

h8_cpu

This specifies the CPU card being used. The value of the property should begin with "Z80" to specify modern Z80 boards. The recognized prefix (starts-with) strings are:

Z80: Generic, early, H8 Z80 board.
Z80_RTC_CLOCK_ORG0: Norberto's Z80 board, 64K, etc.
Z180_RTC_CLOCK_ORG0: Norberto's Z180 board.

The following features may be specified:

DUART: TL16C2550 DUART chip, with different interrupt behavior.
GIDE: GIDE piggy-back add-on.
ROMX: Extended, updatable, 32K ROM (28C256). Includes EEPROM write-enable and full-ROM-map controls via extended port 0F2H (362Q).

The following devices are always present on Norberto's Z80/Z180 boards:

Dual serial ports, "con" and "lp" or "aux". Property "jp4" selects "aux" with value "1", "lp" with "3", disable with "0". Property "jp10" enables "con" with value "1" (disable with "0").
VDIP1 USB-storage adapter (includes FT245R here). Property "jp14" enables VDIP1 with value "1" (disable with "0").
RTC72421 real time clock.
64K (1M for Z180) RAM with ORG0 via extended port 0F2H (362Q).
CPU Speed control via extended port 0F2H (362Q). Property "h8maxclk" selects MAX speed: "10" for 10.240MHz, "16" for 16.384MHz.

The following options (properties) may be selected on Norberto's Z80/Z180 boards:

h8int1: Set to "0" to disable the on-board, H89-style, 2mS clock. Default (if no property) is enable.
h8nofp: Operate without a front panel. No value is required.
h8nmi: Enable H89-style NMI for H8 legacy ports. Intended to be used with "h8_nofp". No value is required.
h89ena2: Set to "1" to add a modification for a second on-board 2mS clock enable, in port 0F3H (363Q) bit 1. Both this bit and port 0F2H (362Q) bit 1 must be set to enable the on-board H89-style 2mS clock. Defends against accidentally having both 2mS clocks enabled. Newest CPU boards have this option built-in. Default (if no property) is no mod.