Difference between revisions of "Schneider RS232 Interface"

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(I/O Ports)
(I/O Ports)
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== I/O Ports ==
 
== I/O Ports ==
  F8E0h Z80 STI Indirect Data Register      Read Write
 
  F8E1h Z80 STI Gen. Purpose I/O Interrupt  Read Write
 
  F8E8h Z80 STI Pointer Vector Register      Read Write
 
  F8ECh Z80 STI USART Control Register      Read Write
 
  F8EDh Z80 STI Receiver Status Register    Read Write
 
  F8EEh Z80 STI Transmitter Status Register  Read Write
 
  F8EFh Z80 STI USART Data Register          Read Write
 
  
* For details on the registers, see [[Z80-STI]].
+
Default I/O addresses are F8E0h-F8EFh (though the interface can be jumpered to use different addresses).
 +
 
 +
F8E0h - Indirect Data Register
 +
F8E1h - General Purpose I/O Data Register (0=Low, 1=High)
 +
F8E2h - Interrupt Pending Register B (write 0=clear, 1=unchanged) ;\
 +
F8E3h - Interrupt Pending Register A (write 0=clear, 1=unchanged) ;
 +
F8E4h - Interrupt in-Service Register B                          ; not used
 +
F8E5h - Interrupt in-Service Register A                          ;
 +
F8E6h - Interrupt Mask Register B (0=masked, 1=unmasked)          ;
 +
F8E7h - Interrupt Mask Register A (0=masked, 1=unmasked)          ;/
 +
F8E8h - Indirect Index and Interrupt Vector Register
 +
F8E9h - Timers A and B Control Register                          ;\
 +
F8EAh - Timer B Data Register                                    ; not used
 +
F8EBh - Timer A Data Register                                    ;/
 +
F8ECh - USART Control Register
 +
F8EDh - Receiver Status Register
 +
F8EEh - Transmitter Status Register
 +
F8EFh - USART Data Register
 +
 
 +
For details on the registers, see [[Z80-STI]].
  
 
== Software ==
 
== Software ==

Revision as of 19:12, 11 May 2010

RS232 Interface for the CPC by Schneider. Schneider is the german distributor for Amstrad CPC hardware (however, this interface seems to be Schneider's own invention, not an Amstrad product).

Note: The uncommon shape of the housing dates back to a Schneider BTX modul (which was being intended to be plugged into Schneider Television Sets). Apparently Schneider produced too many housings, and re-used them for the RS232 interface. Actually, a RS232 interface is very much the same as a BTX interface (the actual BTX modem must be rented separately from Deutsche Bundespost), so even the PCB may be (almost/exactly?) the same for both devices.

Pictures

I/O Ports

Default I/O addresses are F8E0h-F8EFh (though the interface can be jumpered to use different addresses).

F8E0h - Indirect Data Register
F8E1h - General Purpose I/O Data Register (0=Low, 1=High)
F8E2h - Interrupt Pending Register B (write 0=clear, 1=unchanged) ;\
F8E3h - Interrupt Pending Register A (write 0=clear, 1=unchanged) ;
F8E4h - Interrupt in-Service Register B                           ; not used
F8E5h - Interrupt in-Service Register A                           ;
F8E6h - Interrupt Mask Register B (0=masked, 1=unmasked)          ;
F8E7h - Interrupt Mask Register A (0=masked, 1=unmasked)          ;/
F8E8h - Indirect Index and Interrupt Vector Register
F8E9h - Timers A and B Control Register                           ;\
F8EAh - Timer B Data Register                                     ; not used
F8EBh - Timer A Data Register                                     ;/
F8ECh - USART Control Register
F8EDh - Receiver Status Register
F8EEh - Transmitter Status Register
F8EFh - USART Data Register

For details on the registers, see Z80-STI.

Software

Supported by "Starwriter".

Similar (or identical?) Interface

The circuit is very similar (or possibly indentical) to the Tim Riemann's RS232 interface, both circuits are using a Z80 STI, both mapped to the same I/O port addresses. Whether or not the circuits are fully compatible with each other is unknown. Some small details might differ. For example, the clock source being passed to the Z80 STI chip could be different.

Manual (german)

Datasheet

  • A "Z80 STI" is a 40pin MK3801 chip from Mostek. Details on that chip are from the "MOSTEK 1982/1983 Microelectronic Data Book" (kindly made available by John Robertson).
  • The MK68901 seems to be a newer/similar chip (but neither port addresses nor pinouts are backwards compatible).