The weakest link in the Z88 is the connector between the Z88 and the cards. The card edge interface has a long and successful history: for example, in PCI and ISA. Gold is normally used to make sure that it is a reliable connector, but for a number of reasons, this was not used on the Z88 cards. This gives a range of problems including
These effects may be reduced by not removing the cards often. This is now possible as RAM cards should not be removed and Flash cards are erased in the Z88 itself.
There are two sorts of mechanical failure that make the Z88 behave badly.
The first sort gives you unexplained "Memory stack overflow" or FAIL messages at the top of the screen. The most common fault that causes this is when the RAM or Flash card physically comes apart. You will notice this when removing the card from the Z88. It may be a loose fit. What you should find is that the RAM card is made up of two halves and these are coming apart.
You can repair this by
The second sort is that the Device just stops working due to the 'gold' contacts becoming dirty.
The easiest way of doing this is by sliding the card in and out of the connector a few times. If this doesn't improve its performance use a very soft pencil rubber and clean both the connector in the Z88 and the 'gold' contacts.
Be careful though, There is not a lot of 'gold' used on the connector, it is only 'mechanical gold' and you might find that you can clean it off altogether!
Another type of failure is when part of the memory doesn't act like memory. This leads to inconsistent results when checking the size of the Ram with ( CARD). For example, you may have a 512K RAM card in your Z88 but ( CARD) reports that you only have 128K. See Check Z88 Cards.
This program tests 32K, 128K 512K and 1MB RAM cards.
This program erases any files in the RAM area. Ensure that a backup is made before this test is run. See Backing up Files. |
Items Required | Description |
---|---|
A blank 32K EPROM Card to store the applications or files. | |
(Optional) EPROM Eraser to erase the EPROM card (if required). | |
Connecting the Z88 to the Desktop to transfer the programs to the Z88. See Computer Links for more details |
Memtest, consists of four files.
|Procedure;
30 AUG 1988 | 1) -Insert EPROM into slot 3, RESET Z88.
| 2) -RESET Z88, when the screen prompts for the size of
RAM TEST | card to be tested 32,128 ( 512, works ). Open the
| flap and insert RAM card into slot 1.
| 3) -Press the SPACE bar to start. To test again
(2)
from here, unzip and transfer them to your Z88 with a transfer program
There are two ways you can use this program.
#F
|EF
RAMTEST.BAS~E~E
#B
CHAIN
"RAMTEST.BAS"~E
do the following:-
The other sort of memory failure is where certain bits of memory suffer amnesia when you are not reading or writing to the memory.
This is like when you are just storing files in the RAM.
This fault can be found with any program, (zCheck, Zip, Unzip (Z88 Forever) or SqueeZ~88 (Rakewell)) that uses checksums on files. To use it you should:-
A quick way to check the memory is to load a large file and see if it is readable.
The example here is using
The procedure is as follows:-
Select Flashstore J
Move the cursor over the flash.txt file name. Press the key.
The following screen appears, Press the key.
Use the directed keys to exit the application.
Select PipeDream P
FL (File Load)
Select Filer F
Move the cursor over the flash.txt file name if you are testing the memory
Press the key to mark it.
Or move the cursor over the eprlog file name if you are using the Flashtest file
Press the key to mark it.
Press the key to return to Pipedream's file load page. Notice that :RAM.1/flash.txt or eprlog has been entered from the Filer.
Move the cursor down to 'Load as plain text'
Change it to 'Y'
Press the key to Load the file into Pipedream.
Select to display the bottom of the file
Select to display the top of the file again. If this all works, it is looking good.
When Flash cards are assembled, they need to be tested to ensure that all the connections are made and chips are working correctly. Flashtest has been designed to test four different types of flash cards in the Z88. These are:-
If the RAM is detected in the 512K cards, a RAM test is also run.
A 32K EPROM card is being used to store two applications that are 16K each. These are Flashstore and Flashtest.
Flashtest erases any files in the RAM area and FORMATs the complete Flash Card. All applications and files in the file area will be erased. Ensure that a backup is made before this test is run. See Backing up Files. |
These are the same as the Main Prerequisites as above.
Unzip Flashtest 32, the file and transfer the five files to the Z88.
The Z88 needs to have the following cards as a minimum configuration.
Slot 2 may have another Flash card with the Computer Link in it.
The files are shown here displayed in the Filer are:-
To run the program, do the following:-
The following screen is displayed.
EPROMs can only be programmed in Slot 3.
Press V. followed by
If the EPROM is properly erased the following screen is displayed.
If an error message is displayed, the EPROM should be removed and erased again with the EPROM Eraser until it passes this test.
From the main screen, Select
The screen will flash a few times until the following screen is displayed. If any programming errors are given, the EPROM will need to be erased and this procedure needs to be repeated from Verify EPROM banks properly erased.
Ensure that all important files are backed up before testing the Flash card. All applications and files on the card will be removed. See Backing up Files. |
Flashtest is either selected from the INDEX screen it in the APPLICATIONS window, or use ZT to start it directly.
otherwise the stating screen will be displayed.
To ensure that Flashtest is not started accidentally, the user needs to type asdf to proceed with the test. |
Depending on the size and type of Flashcard is being tested, different start screens will be displayed. This happens too quickly to screen capture but at the end of the test a summary is displayed. This is for the 1M INTEL card.
This is for the newer AMD card.
To view the full report, which has been saved in a file can be viewed using Pipedeam.
The top part of the report, followed by
the end of the report.
This card has RAM. This gets recognized by the operating system as soon as it is inserted into the Z88. When the card is removed, a Hard Reset is required. Ensure that all important files are backed up before removing the card. The Flash card tested may be used, using Flashstore, saving the files into the empty file area. See Backing up Files. |
When testing this size, it is done in two parts. First the Flash chip, followed by a choice on whether to test the RAM.
Remember to change N to Y if the RAM is to be tested, otherwise the default of No will be selected. |
Testing the RAM takes some time, but eventually the summary page will be displayed.
Just because you get the message that it has "Successfully tested RAM memory with no errors," it is up to you to check how much RAM the Z88 thinks it has got by selecting the followed by CARD. It should read 512K. |
To view the full report, which again has been saved in a file can be viewed using Pipedeam.
The top part of the report, followed by
the end of the report.
You can contact Rakewell and see if it can be repaired.