WonderMCA: Usage guide

This page follows what you do, in the order you do it. The screenpad is on the screenpad reference. Every setting is explained on the configuration reference.

Before you start. The card is installed and configured with the Reference Diskette (hardware and installation), the firmware is current (firmware and CPLD update) and the microSD card holds your images (microSD card preparation).

1. Power on

1. Switch the PS/2 on. The PS/2 counts its memory and scans its adapters. With a screenpad, the display shows its logo, then the code of the POST step in large digits, with its meaning under it.
2. When the PS/2 reaches the adapter ROM of the card, the card prints its banner on the screen and waits:

The lines of the banner, from the top:

Banner	Meaning
WonderMCA BIOS (Date 2026-10-21 Rev 08ED) – F8 to skip	The date and the revision of the option ROM. Press F8 in the first five seconds to skip the card completely
– Init: …	One dot per step of the start-up of the card
ROM @D000 – Port : 2A0 – IRQ : 5 – Boot Count : 1	The segment of the option ROM, the command port, the interrupt the card uses to talk to the option ROM, and how many times the card has booted the PS/2 since it was powered
XMS : 4096kB (planar 1920kB)	The extended memory of the card and the memory of the system board. XMS : None when it is off, XMS : Fail when the PSRAM failed its test
MicroSD : Ok	The microSD card was read. Fail when it was not
USB : Ok	The USB host started. Disabled when it is off
Config : Ok	The settings were read
Network : Ethernet Mac: …	None, WiFi, Ethernet or USB Eth, with the MAC address when the adapter is up
USB : 2 devices, then one line per device	What is plugged into the USB-A port, such as 1: USB keyboard and 2: USB mouse
> Press S for Setup, Other to continue 5	The countdown, 5 seconds (1 second when Fast Boot is on)

A minimal configuration prints fewer lines:

With a WiFi network, the Network line shows WiFi and the MAC address of the card’s radio:

On a Model 50Z with 1 MB on the system board, the XMS line reads (planar 1024kB):

3. Press S to open the setup menu (section 3). Press A to boot from the floppy first. Any other key, or no key, continues.
4. The card prints Emulated Memory – None and the list of what is mounted:

Line	Meaning
FDD0 : DOS622 [1440KB]	The image in floppy A: (FDD1 is B:) and its size
HDD0 : DISK1 [ 512MB] – C:1040 H:16 S:63	The image of hard disk 0 (HDD1 to HDD3 follow), its size and its geometry: cylinders, heads, sectors
CD : WIN95 [ 612MB]	The CD image

When a configured image cannot be mounted, its line shows the reason in brackets instead of the size: No FLOPPY folder, No HDD folder, Image not found or Bad image. The red LED of the screenpad blinks.

Two special starts

• F8 to skip. Press F8 during the first five seconds of the banner. The screen says > F8 detected: PMBIOS skipped and the PS/2 boots without the card’s drives, its memory and its devices. Use it when a setting of the card stops the PS/2 from booting.

• USB DEBUG Mode. The option ROM can print USB DEBUG Mode: Connect a terminal to the USB Serial Port. and wait for a terminal before it goes on. That screen belongs to the PicoMEM card the firmware comes from: the WonderMCA firmware never asks for it. If you see it, the card runs a firmware that is not a WonderMCA build.

2. The boot prompts

If Boot Code is on (Disk page of the setup menu), the card boots the PS/2 itself:

The countdown is 3 seconds (1 second when Fast Boot is on).

Key	What happens
A or Q	Boots from the floppy first, then from the hard disks
C	Boots from the CD-ROM image (CD-ROM)
B	Goes to the Basic or ROM of the PS/2 (INT 18h)
R	Restarts the PS/2
No key	Boots from the hard disks first (drive 0, then drive 1), then from the floppies (A:, then B:)

The screen then shows which drive boots:

Messages you can meet:

Message	Meaning
: Incorrect MBR	A hard disk has no boot signature. The card goes on to the next drive
CD: not bootable (no El Torito catalog / no disc)	You pressed C but the disc has no boot catalog, or no disc is mounted. The normal boot order goes on
> No Boot Disk found – Insert a Floppy and Press any Key.	No drive could boot
Boot failed : Select another image or disable the WonderMCA Boot Code.	The boot failed. The card prints its banner again, with Boot Count : 2, and the setup prompt
> Boot: Start Legacy Boot Strap	Boot Code is off: the PS/2 boots as if the card had no boot code

3. The setup menu

Press S at the banner. The title bar reads -= WonderMCA BIOS =-. The menu has seven pages:

Main | Disk | Audio | Network | USB | POS Register | Tools

The bottom of the screen shows the keys:

Key	What it does
Left, Right	Change page. Left on Main goes to Tools, Right on Tools goes to Main
Up, Down	Move between the items of the page. The arrow > marks the item. Up on the first item goes to the last, Down on the last goes to the first
PgUp, PgDn	First and last item of the page
Enter, +, –	Change the item: toggle On and Off, or open a list
Esc	Leave the menu

When you leave the menu with Esc, the card saves your changes to the microSD card and the boot goes on. USB, network and audio settings apply when the card finishes its start-up.

3.1 Main

Entry	What it shows or does
BIOS Rev	The revision of the option ROM
MCA Bus	16Bits or 8Bits: the data bus width of the firmware, make sure CPLD is aligned with the MCA Bus
Total Memory	One line: the total memory of the PS/2 in MB (extended memory of the card included), the number of floppy drives and the number of hard disks
Board IRQ	The interrupt the card uses to talk to the option ROM
Fast Boot	On or Off. On shortens the waiting time at the two prompts to 1 second
Use RTC	On or Off. On: the clock of the card sets the DOS clock at boot
RTC Date/Time	The clock of the card, as yyyy-mm-dd hh:mm:ss

3.2 Disk

Entry	What it does
Floppy Drive A:, Floppy Drive B:	Choose a floppy image
HD Drive 0: to HD Drive 3:	Choose a hard disk image
CD-ROM:	Choose a CD image
Boot Code:	On: the card runs the boot prompts. Off: the PS/2 boots by itself. The page says – Set Off for XTIDE/Disk BIOS
New Disk Image:	Select opens the dialog that creates a new hard disk image

At the bottom the page reminds you: Store the images under FLOPPY, HDD\ and CDROM\ (.iso) Folders and Images files name <13 character and extention .img. If the card cannot be read, the page shows Warning: SD not present or error.

Choosing an image. Enter on a drive opens a list:

• The first line, on the first page, is -=None=-: it empties the drive.
• At the top of the list, [[SD]] and [[USB]] choose the volume. Inside a volume, folders show in square brackets, [OS2]. Enter on a folder opens it. [..] goes up.
• A floppy shows its size in KB, a hard disk or a CD its size in MB. A name that is too long shows Error as its size and cannot be selected.
• A page holds 16 entries. The page number shows at the bottom right, such as 1/2.

Key	What it does
Up, Down	Move. Down at the end of a page goes to the next page. Up at the top goes to the previous page, on its last entry. Up on -=None=- goes to the last entry of the last page. Down on the last entry of the last page goes back to -=None=-
PgUp, PgDn	Previous and next page
Enter, Space	Select
Esc	Cancel

The floppy images and the CD image change at once. A hard disk image is mounted at the next start of the PS/2.

Creating a new hard disk image. See section 6.

3.3 Audio

Entry	Values	Notes
Output:	On, Off	The whole audio output of the card
Adlib:	On, Off	> Port 388h
Sound Blaster:	On, Off	When On, the row shows the port, the interrupt and the DMA channel read from the configuration of the PS/2: > Port 220 IRQ 7 DMA 1
Gravis Ultra S.	On, Off	Cannot run with the Sound Blaster. When On, the row shows the same resources
CMS:	Off or a port	No effect on the WonderMCA
Tandy:	Off or a port	No effect on the WonderMCA
Mindscape:	Off or a port	No effect on the WonderMCA. > May conflict with XTIDE and NE2000

The page says For other options see documentation. See Sound and game port.

3.4 Network

Entry	Values
Network:	None, Ethernet, WiFi, USB Eth
IRQ:	3, 5, 6 or 7. The page says – NE2000 IRQ: 3/5/6/7
Port:	300h. The page says – NE2000 port range is 32 bytes
Status:	The state of the connection
MAC:	The MAC address
SSID : and Signal :	The WiFi network name and its strength, when WiFi is on
[Refresh]	Reads the state again

Going from WiFi to Ethernet, or back, in one power cycle is refused with Power cycle needed. See Network, which shows the page for each network type.

3.5 USB

Entry	Values
USB Host:	On, Off. The page says – PC Joystick is on Port 201h
USB Joystick:	On, Off
USB Keyboard:	On, Off
USB Mouse:	On, Off

See USB devices.

3.6 POS Register

The page POS Registers shows the Register dump of the card: the slot, the adapter ID 0xDEAD, the eight POS bytes, and the decoded settings Joystick, DMA Prio, IRQ and I/O Base. [Refresh] reads it again. Use it to check that the Reference Diskette settings reached the card (hardware and installation).

3.7 Tools

Entry	What it does
PicoMEM Infos	Shows the board identity (PicoMEM Board ID: 20), the processor clock (PCPU Clock (RP2350): 280MHz), the PSRAM (QSPI PSRAM: 8MB, 93MHz), the interrupt, and the Detected ROM List: every option ROM the PS/2 found, with its segment, its size and its checksum
ROM/RAM Dump	Copies each option ROM to a file ROM_<address>.BIN and the first megabyte of memory to RAM_DUMP.BIN, at the root of the microSD card. The page prints one line per ROM, then > Full RAM Dump to RAM_DUMP.BIN (1MB) Done and > Completed

4. Mounting and swapping images

What	Where	When it takes effect
Floppy A: or B:	Setup menu, screenpad, wmctrl	At once. DOS sees the new disk
CD-ROM	Setup menu, screenpad, wmctrl	At once
Hard disk 0 to 3	Setup menu, wmctrl	At the next start

To change a floppy while DOS runs, use the screenpad: Disk > Mount floppy, then A: or B:, then the image (screenpad reference). Or run wmctrl disk fdd a <image> in DOS (section 7).

DOS refreshes its view of the diskette when it is idle. If DIR A: still shows the old disk, run FDSWAP from the tools floppy, then DIR A:.

5. Booting from a CD

Press C at the boot prompt. See CD-ROM.

6. Creating a new hard disk image

1. Open the Disk page and select New Disk Image: Select, then press Enter.
2. The dialog asks New Disk Size (MB):. Type the size and press Enter. The size is brought to between 10 and 4096 MB.

3. The dialog asks Disk Name:. Type a name of 13 characters at most and press Enter. An empty name cancels.
4. The dialog shows Creating Image : n MB, then Done, or Error: with the reason. Press any key.
5. The image is HDD/<name>.img on the microSD card. Select it as a hard disk (section 3.2).
6. Restart the PS/2, boot from a DOS floppy, then run FDISK and FORMAT on the new disk.

The reasons of an error: Image already exist, HDD directory missing, uSD Full, Write to file failed, Disk Operation failed.

8. Saving your settings

• The setup menu saves when you leave it.
• A floppy or CD mounted on the screenpad is saved at once.
• Settings you change on the screenpad pages Sound, Network and Disk config apply to the running card when you press RET. To keep a setting for the next start, also set it in the setup menu.
• wmctrl saves when you leave its menu with Save or press F10, and after every command.
• config.txt keys win over the saved settings for the keys they set (configuration reference).

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