Sideways Roms; Cp/M Plus Terminal Emulator - AMSTRAD cpc 6128 User Instruction

It is intended that the part of the address AO - A 7 should reflect the type of external
I/O device, and that address lines A8 and A9 may be decoded to select registers within
the I/O device. Of the remaining address lines, only A10 must be decoded (as low)
whilst lines All to A15 are high. Thus each device may have registers addressed as
&F8??, &F9??, &FA??, and &FB??, where ?? is in the range DC to DF for
communications interfaces, and EO to FE for other user peripherals.
Note that Z80 instructions which place the B register on the upper half ofthe address
bus (A15 - A8) must be used.
Sideways ROMs
Provision is made for additional ROMs to be selected in place of any part of the
on-board ROM. The address arbitration and bank selection logic will be contained in
a module connected to the expansion bus, but all the signals required are brought
to
the expansion bus.
Part 15: CP/M Plus Terminal Emulator
In part 1 of this chapter, a table of control characters (together with their respective
actions) was illustrated. These actions are performed when text is sent to the screen
by BASIC or CP/M 2.2, and were chosen both to be simple to use and to reflect the
facilities available in the Firmware Text VDU. These facilities are unique to
AMSTRAD computers, and software must therefore be adapted to their use.
In the Business and Commercial environment ofCP/M Plus software, it is normal to
expect a range of 'standard' Text VDU facilities in order that software is easily
portable and 'installable' from one machine to another. The CP/M Plus
implementation on the 6128 includes a Terminal Emulator which provides facilities
very similar to a Zenith Z19/Z29 VDU. The installation procedure for CP/M Plus
software will normally include, as standard, an option for this type of terminal.
The facilities offered by the CP/M Plus Terminal Emulator include many of those
previously offered by the Firmware Text VDU although different control codes are
required.
There are a considerable number of new and more sophisticated operations.
Characters in the range &20 to &FF are displayed at the current cursor position. If
the cursor is not atthe right-hand column, then it is moved right by one column. If the
cursor is at the right-hand column and wrapping is enabled, then it is moved to the
left-hand column on the next line, scrolling up if necessary.
Chapter 7 Page 48 For your reference ....