07-06-2020, 08:46 AM
(07-06-2020, 12:20 AM)max_imp Wrote: eprom is an acronym ( abbreviation ) for; Erasable Programmable Read Only Memory.
It consists of a special memory chip which is programmed under special circumstances which normally never happen
in a working computer and can not be accidentally changed by the computer, it's pretty safe once programmed.
The memory is in fact a lot of fet transistors that get "set" to either a one or a zero, ( conduct current or not ) they all have a specific place in the chip and can be "addressed" by a request to read the contents of that address, ( an instruction: do this....... , a value of something "max speed", a message to the user "fault code" etc. ).
In our case it controls how our bike behaves and precisely sets the rules how the bike responds, wrong instruction; it mis-behaves according to that instruction.
The eprom can be removed, re-used in another piece of equipment ( ecu ) and re-programmed, since the transistors remain in their on or off state there is no need for a battery to "refresh" the transistors like is done with conventional "ram" memory in a pc, which loses it's contents when the power is switched off ( Random Access Memory ).
However these days the use of an Eeprom ( Electronically Erasable Programmable Read Only Memory ) is used instead, the advantage is that it can be programmed and re-programmed when the computer is running ( but in a special state to access the memory only ) without the need to replace the chip ( when it's soldered inside the waterproof e.c.u. ).
So a usb programming lead is used to write new software into an e.c.u.
As lord Popgun emeritus explained.
Which brings me to the next question;
Since this thread has elaborated somewhat is it possible to extract the relevant parts like pictures and ways to repair the new methods in a compact Read Only format under a similar title such as; cb1100 idle speed instability repair advice?
Max, this is an attempt to do that. Is it what you had in mind, or have I gone too far?