prindle@nadc.ARPA (01/05/87)
There were essentially 4 versions - one dated August (something or other), and three dated 4 Dec 85, 6 Dec 85, and 8 Dec 85. The 4 Dec 85 version was the first to support RS-232 serial I/O; this bore a RED warning message when booted to the effect that it was a Beta-Test release. The 6 Dec 85 and 8 Dec 85 versions are essentially identical, the former being released via various BBS systems, the latter being distributed on diskette by Commodore - these both support RS-232 serial I/O and the 1700/1750 RAM Expansion units as ramdisk M:. There have been no further releases (actual release date of the 8 Dec 85 version was in the spring of 86.) Along with the newer versions of the BIOS are supplied two new BIOS specific utilities: CONF.COM which allows on-the-fly patching of various BIOS configuration options (such as screen colors, RS-232 baud rate, keyboard sampling rate, keyclick volume, printer translation mode, etc.); and C1571.COM which speeds up writes to the 1571 drive by bypassing read-after-write validation. Also of interest are releases of IMP, MEX, MODEM7, and BYE which utilize the added "pseudo" UART port. As a result of the method necessary to implement the RS-232 I/O, namely running an interrupt routine at 3 times the baud rate, all of the newer versions cause the 128 CP/M to run anywhere from 6% to 300% slower than the old August version - a rule of thumb to avoid slow-down: set BAUD to 110 when not using the RS-232 port (it defaults to 300); this minimizes the interrupt rate without making the keyboard slug- gish. The new keyboard scan routine, integrated with the RS-232 interrupt routine, effectively eliminates all those ugly key-bounce problems common to earlier versions - keyclick added too! All the necessary files to update to the newest version are available on SIMTEL20 CP/M archives in directory PD:<CPM.C128>. These are: NEWSYS.COM - Installs new bios into CPM+.SYS C128-NEW.DOC - Doc on above C128-NEW.IRV - More doc C128CNF3.LBR - CONF.COM and CONF.HLP files C1571-2.COM - Latest (less buggy) C1571.COM file C128-MEX.COM - MEX for 128 IMP-C128.COM - IMP for 128 BYE128.LBR - BYE for 128 BYE128.DOC - How to use BYE128.LBR M7* - Various MODEM7 overlays for 128 CP4-C128.LBR - Kermit for 128 Sincerely, Frank Prindle Prindle@NADC.arpa