4 - Odd Bin

Finding Z88's Version Number

There are three UK version numbers. To find out which one you are using you have to do the following:-

1. Press the  key.
2. Press the  key
3. Press the key

You should now see which version number you are running. This one is Version 2.2, the original British one.

This one is Version 4.5 B4, downloaded from this site.

Magic Numbers

The Z88 uses an 8-bit microprocessor. What does this mean to you? Not a lot? What should it mean to you?

Like a mileometer in a car that only has say eight numbers, the maximum number you can show on it is 99999999. Add one to that number and you will see 00000000. Although that can give you a low mileage car, it also gives you the wrong result.

There are two ways you can use this `limited number'.

The first way is like the car mileometer example where you can count POSITIVE numbers from 00000000 to 99999999.

The second way gives you half the numbers you had before but can use both POSITIVE and NEGATIVE numbers. Numbers read the same but can mean different things. Here are a few THREE DIGIT examples to show you what I mean.

Changing to Binary

Having only some numbers give limitations. Unlike the THREE digit mileometer which can give us numbers up to 999, the Z88 uses binary numbers.

The maximum number of an eight bit number is 256 or 127 if it uses the positive/negative number. See Page Length Limitations in PipeDream's bugs. 

OZ Gobbles Memory - Slowly

When you start an application, OZ - the Z88's operating system allocates some memory for that application to run in. In an ideal world what you would like to see is it returned to the pool of spare memory when the application has finished with it.

This is what is supposed to happen when you (KILL) the application. What does our friend OZ do? He sometimes keeps a bit of it for himself and looses it.

What he has lost is what the technocrats call `handles.' This is one reason that you may find memory disappearing, it is not because your RAM pack has sprung a leak. OZ has lost his handles.

You can get this memory back by periodically saving all your files - (see Back-up) doing a Hard Reset and loading all your files back again. Alternatively you could try a Soft Reset or remove an EPROM / ROM card which has been reported to sort out handles.

PipeDream

Mixing up Plain Text files with PipeDream format

If you Load a file into PipeDream that is not the correct format you will see your file loaded incorrectly. It is easy to fix once you know what is wrong.

The most common mistake that is made is to load a `Plain Text' file into PipeDream without loading it as a `Plain Text' file.

You will see the file only in Column A, twelve characters wide. If this happens, load the file again, but use the `Load as Plain Text' option set to `Yes' this time.

Saving a BBC BASIC program to a text file

Load the program into BBC BASIC. Then type

+S   

This starts writing a CLI file. Then type

LIST

This lists the program whilst writing the CLI file.

When listing stops, stop writing the CLI file  by typing 

-S

The output has been written in 

:RAM.-/S.sgn

This text file can either be loaded into PipeDream or downloaded to desktop computer.

More Static Electricity

Static electricity is all around us. It does irreparable damage to low current electronic circuits, such as those used in the Z88. It can be also responsible for the Z88 doing a Soft Reset when you are inserting the Mains Adapter lead.

Inserting Mains Adapter lead

Before plugging in the lead, do the following:-

1. With your right forefinger, touch the metallic Serial Port socket.
2. With your left hand get hold of the Mains Adapter lead and touch the metal plug.
3. If you are still alive, plug the Mains Adapter lead into the Z88.

Sharing Same Power Source - WARNING

It might be tempting to run your Z88 and printer from the same power source. Using a car or motor boat battery source for example. There are many DC convertors that can convert from 12v to about 6.8v so in theory, save on battery costs.

There is a major problem with this and that is that the positive pin of the power socket on the Z88 is connected internally to the 0v or Ground pin of the RS-232 connector. If you connect two items that are sharing the same power source you short out the power supply.

This does not happen when you are using separate mains adapters for each item because each power source is isolated from the other. You could run one of them from this supply but not both.

At worse you will damage both the Z88 and the printer so DO NOT SHARE POWER SUPPLIES.