| Processor | CMOS Z80 running at 3.2768 Mhz. |
| Circuitry | Most complex jobs are done by the BLINK gate array chip. |
| Memory | The Z88 can address up to 4M of memory. This is achieved by dividing the 64K address space of the Z80 processor into 4 x 16K segments. Each segment can then be assigned to any of 256 x 16K banks, thus allowing a total of 4M. The first 64 banks are assigned to internal memory and the three card slots at the front of the machine are assigned 64 banks each. |
| RAM | 32K internal, expandable by addition of external RAM cards. 512K RAM may be soldered as internal RAM replacing the 32K standard (requires also retracking of circuitry). Current available are 128K, 512K and 1MB RAM cards. |
| ROM | 128K internal (some Z88 portables have pre-fabricated ROM chips, most others use a 128K EPROM), but also bootable by inserting Eprom or Flash Card with OZ image in slot 1. ROM by definition contains the operating system (OZ), built in applications and hooks for external applications to be integrated into the system. The underlying hardware allows the internal ROM to be expanded to 512K. However, modification of the motherboard is needed to add the extra address lines, since only 128K is addressed. |
Screen | 640x64 pixels, usually divided into 104x8 6 pixel wide characters and 16x64 pixels of status information at the far right of the screen. |
Serial Port | RS232 port, configured as DTE, for connecting a printer or communicating with other devices. Tx, Rx, CTS, DCD and RTS can be independently set and read, both software and hardware handshaking are supported. The serial port runs at the following baud rates: 75, 300, 600, 1200, 2400, 9600, 19200, 38400. |
Power supply | Internal batteries (4xAA, alkaline) or external 6.5V DC supply. Note NiCad's are not suitable, losing their charge too quickly at the end of their life, thus putting data at risk. Also even if the Z88 is running off the power supply, batteries should be installed. This safeguards against power failure etc, which may cause data to be lost in a machine with no batteries. |
EPROM/Flash Cards | Slot 3 contains circuitry for programming EPROM cards. This circuitry unfortunately means that RAM cards in slot 3 consume much more power than in slots 1 and 2. It is recommended that slot 3 is, therefore, not used for RAM. Note also that when the machine is powered up from cold (eg. for the first time) there is a small chance that an EPROM in slot 3 will be written to and corrupted. Therefore, it is advisable to remove EPROMs if the Z88 has had no power and you are about to apply it. 32K, 128K and 256K EPROM Cards are available. Rakewell supplies 1Mb Flash cards that may be updated in all slots (including erasing/formatting). Intel 28F generation Flash cards may be programmed and formatted in slot 3 only. AMD 29F generation flash cards may be formatted and programmed in all slots (including slot 0). |
Software | OZ operating system. Index (application coordinator), Filer (RAM filing system), Panel (for system settings), PrinterEd (for printer settings), Imp Export (for communication with other machines), Terminal (VT 52 compatible), Alarm, Clock, Calendar and Calculator. Also three fully blown applications: PipeDream (wordprocessor and spreadsheet), Diary and BASIC (a version of BBC BASICZ80). V4.5 OZ is added with EazyLink (remote file management from other computers), XY-modem protocol in Imp/Export and FlashStore (file backup/management on Flash/Eprom File Cards). |
Expansion | Three card slots at the front of the machine for RAM or EPROM/FLASH Cards. Expansion connector available for OEM applications, but is normally sealed. |
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