It’s now time to open the box.
The CE-158 is a nice extension with a multi-board construction.
On the bottom there is the main electronic board with the LH5801 multi i/o IC.
On the middle there is the RS-232C interface.
And on the top there is the Centronics interface.
The battery pack is 500mA/h 4,8v.
Here are the Sharp specifications :
And the Service manual :
I have found the connexion cable for 2 CE-158 in a chinese book :