B&B Electronics SPP-100 - Manual - Manual (Page 49)

8. Programming the SPP-100
8.1 Program Registers
The program registers of the SPP-100 occupy eight contiguous bytes of
I/O address space. In addition, the Extended Control Register (ECR) is
located at an offset of 402h from the I/O space base address. By writing
this Extended Control Register, one of three parallel port modes may be
configured: standard (unidirectional) parallel port mode, bi-directional
parallel port mode, or EPP (Enhanced Parallel Port) mode. Setting the
EPP mode through the configuration software (the Enabler or the Client
Driver) overrides the value written to the Extended Control Register.
After the correct mode is configured, the program registers may be
programmed to control the operation of the SPP-100. The table below lists
the program registers along with their offsets relative to the I/O space
base address at which the SPP-100 is located:
+ Extended Control Register (ECR) R/W 402h
* EPP Data Register 3 R/W 7
* EPP Data Register 2 R/W 6
* EPP Data Register 1 R/W 5
* EPP Data Register 0 R/W 4
* EPP Address Register R/W 3
Device Control Register (DCR) R/W 2
Device Status Register (DSR) R/W
(in standard and bi-directional
modes, this register is read only)
1
Data Register R/W
(in standard mode, this register
is write only)
0
Register Read/Write Offset
Figure 15. SPP-100 Program Registers Table
* NOTE: These registers are present only if EPP mode is selected.
+ NOTE: Present only in Revision E and earlier PCMCIA Cards
Quatech Inc. 8-1