I came across a disk image of LCSI Sprite Logo and thought I'd see if it could work.

Modified ezcgi for different addresses:

Code
uint8_t a2bus_ezcgi_device::read_c0nx(uint8_t offset)
{
        switch (offset)
        {
                case 0:
                        return m_tms->vram_read();

                case 2:
                        return m_tms->register_read();
        }

        return 0xff;
}

void a2bus_ezcgi_device::write_c0nx(uint8_t offset, uint8_t data)
{
        switch (offset & 0x3)
        {
                case 1:
                        m_tms->vram_write(data);
                        break;

                case 3:
                        m_tms->register_write(data);
                        break;
        }
}

and I can see it does something, but it doesn't work correctly. Looking at pictures of the board, there's a 2k rom and it must be using some code there. Curiously, it doesn't appear to use IOSEL or IOSTB to access the rom, but rather INH.

[Linked Image from i.imgur.com]

ruh-roh!

[Linked Image from i.imgur.com]