Baumwell Macintosh XL Hardware Information

Macintosh XL Hardwaire Information See also: Lisa r.lardware Manual Written by: Mark 13aumwell 16 May 1985 This document covers Macintosh XL information that is either incorrectly documented or not documented elsewhere . .ILQ_Space Adresses The Lisa Hardware manual shows incorrect addresses for locations in the 1/0 space such as the expansion slots, floppy disk controller, serial ports, parallel ports, keyboard/mouse control, etc. The addresses are listed as OOxxxx in the manual, but should be FCxxxx. As an example, refer to figure 2-6 (System 1/0 Space Overview} in the lisa Hardware manual . The correct addresses for the expansion slots are (all in hexadecimal}: AQQr~~§ FCOOOO FC2000 FC4000 FC6000 FC8000 FCAOOO - FClFFF FC3FFF FCSFFF FC7FFF FC9FFF FCBFFF Function Expansion slot #1 Low Decode Expansion slot #1 High Decode Expansion slot #2 Low Decode Expansion slot #2 High Decode Expansion slot #3 Low Decode Expansion slot #3 High Decode Also note that while the 1/0 space adresses are in the range FCxxxx, the Boot ROM addresses are in the range IFExxxx. Reading the Boot ROM version number To checJs the version numb1er of the Boot ROM, display location FE3FFC for 4 bytes. If you display it from LisaBug, the display looks something like this: OOFE3FFC 0248 The version number is 0248, or 2.48. Note that 48 hex =ASCII H. Therefore, the ROM revision is H. Note the thE~ Boot ROM version number and the Floppy ROM version number are displayed in the upper right hand corner of the Macintosh XL screen during the self test. For example if H/88 was displayed on the screen during the self test, the Boot ROM is revision H and the floppy ROM version number is 88. Macintosh Technical Support page 1 of 3 Macintosh XL Hardware Information ,,,...- '·. Bfiading Parallel Interface Gard ROM version numbers Note that if a Parallel lnt1arface Card is installed, you can check its ROM version number by adding FF8 to the start of the Low Decode address of the slot the card is in and then displaying the resulting location for 4 bytes. To interpret the version number, look at the low order byte, of each word. For example, to check the ROM version number of a Parallel Interface Card in slot 2, display location FC4FF8 for 4 bytes. If you display it fr9m LisaBug, the display looks something like this: OOFC4FF8 0001 0007 Since the ROM is on the lower half of the data bus, the upper half of the data bus should be interpreted as don't cares. Therefore, the version number is 0107, or 1.07. Parallel Interface Card VIA offsets Each Parallel Interface Card has two 6522 Versatile Interface Adapters (VIAs}, one for each parallel port. The address of the VIAs is found by adding constants to the Expansion slot decodes as described below. Add 2000 hex to the slot low decode to get to the lower VIA base address. Add 2800 hex to the slot low decode to get to the upper VIA base address. For example: FC2000 is the slot 1 lower VIA base address. FC2800 is the slot 1 upper VIA …