CP/M 5 1/4 Inch Floppy Formats ------------------------------ B.Eiben 30-Sep-85 Update 3 27-Dec-87 [Updates by Hal Bower @DCA-EUR - old [wrong] values on top of corrected ones.] [Updates by Bill Duerr, for Kaypro quad, corrected skew facter.] A "sad" but "happy beginning" story - since most of the time one can "work around" these incompatibilities via MODEM, KERMIT, or any of the other file-transfer programs (by the way MUCH MORE SUCCESSFUL too, since one doesn't get hurt by floppy-drive incompatibilities - not too many drives are calibrated !!) This comprises my "current knowledge" in trying to READ foreign floppies on DEC's Rainbow and VT180 with "non-standard" drives - formatting (and writing) foreign floppies is a story in its own! One CAN NOT reliably write with a 96 tpi drive 48 tpi formats - and one has to know MORE about the internal formatting. As an example DEC's micro's (and others) format sectors in ascending order per track - and then use skew tables to overcome latency for read/write; Kaypro (and others) format sectors "skewed" (the controler "finds them" as easy as the other ones) and then don't need internal software skewing, since latency is taken care of by the controler. To make matters "worse" densities (and sectors/track plus skewing) can change between BOOTs-blocks and the rest of the floppy - plus double-sided floppies can have sectors (on the "UPPER" and "LOWER" side) arranged differently per track. See above - a "sad" story !! NO GUARANTEE for the following data (I double-checked it) - Feedback requested regarding additions and corrections to: EIBEN@DEC-MARLBORO (Who will update and post) The table lists DPB-values and skew-tables. Beware DSM and AL0 are HEX, DRM values are mixed! The MRK-byte (hex) tries to "extend" the DPB info with the following : 7 6 5 4 3 2 1 0 | | | | | | \ / | | | | | | 00 => 128 byte sectors | | | | | | 01 => 256 byte sectors | | | | | | 10 => 512 byte sectors | | | | | | 11 =>1024 byte sectors | | | | \ / | | | | 00 => 1K allocation blocks | | | | 01 => 2K allocation blocks | | | \ reserved | | \ 1 if continous sectors from upper track to lower track | | 0 if same sectors on both sides ( "normal" method ) | \ 1 if double sided floppy \ 0 single density 1 double density | | S|B| B|E| D | D | A |A|C |O| | M| | | P|S| L|X| S | R | L |L|K |F| | R| Name |Type| T|H| M|M| M | M | 0 |1|S |F|Sector Skew | K| ======================================================================= Actrix |SSDD|36|3| 7|0| AA| 63| C0|0|16|2|1,4,7,2,5,8,3,6,9 |82| ----------------------------------------------------------------------| [ the following four AMPRO entries also by Hal Bower -- thanks... B.E.] Ampro |SSDD|40|4|15|1| 5E| 63| 80|0|16|2|1,2,3,4,5,6,7,8,9,10 |86| 48 tpi| | ----------------------------------------------------------------------| Ampro |DSDD|40|4|15|1| C2|127| C0|0|32|2|1,2,3,4,5,6,7,8,9,10 |C6| 48 tpi| | ----------------------------------------------------------------------| Ampro |SSDD|40|4|15|1| C2|127| C0|0|32|2|1,2,3,4,5 |87| 96 tpi| | ----------------------------------------------------------------------| Ampro |DSDD|40|4|15|0|18A|255| F0|0|64|2|1,2,3,4,5,6,7,8,9,10 |C7| 96 tpi| | ----------------------------------------------------------------------| Cromemco 520 | see Xerox 820 I SSDD | ----------------------------------------------------------------------| DEC VT180|SSDD|36|3| 7|0| AA| 63| C0|0|16|2|1,3,5,7,9,2,4,6,8 |82| ----------------------------------------------------------------------| DEC other|SSDD|40|4|15|1| C2|127| C0|0|32|2|1,3,5,7,9,2,4,6,8,10 |86| Rb/DM/Pro96tpi| | | ----------------------------------------------------------------------| Eagle IIE|SSDD|40|4|15|1| C2|191| E0|0|30|2|1,3,5,2,4 |87| -2 96 tpi| | | ----------------------------------------------------------------------| Heath 89 |SSDD|32|3| 7|0| 97|127| F0|0|32|2|1,2,3,4,5,6,7,8,9,10, |81| | |11,12,13,14,15,16 | | ----------------------------------------------------------------------| Heath 89 |DSDD|32|4|15|0| 9B| FF| F0|0|40|2|1,2,3,4,5,6,7,8,9,10, |C5| | |11,12,13,14,15,16 | | ----------------------------------------------------------------------| Heath/MagnSSDD|36|4|15|1| 52| 5F| C0|0|18|3|1,2,3,4,5,6,7,8,9 |86| ----------------------------------------------------------------------| Heath |SSXD|40|3| 7|0| BD| 7F| F0|0|32|2|1,2,3,4,5 |83| ----------------------------------------------------------------------| Heath |DSXD|40|4|15|0| C2|255| F0|0|64|2|1,2,3,4,5 |C7| ----------------------------------------------------------------------| Heath 89 |SSDD|32|4|15|1| 9B|127| C0|0|32|2|1,2,3,4,5,6,7,8,9,10, |85| 96 tpi| |11,12,13,14,15,16 | | ----------------------------------------------------------------------| Heath 89 |DSDD|32|4|15|0|13B|255| F0|0|64|2|1,2,3,4,5,6,7,8,9,10, |C5| 96 tpi| |11,12,13,14,15,16 | | ----------------------------------------------------------------------| Heath 89 |SSXD|40|4|15|1| C2|127| C0|0|32|2|1,2,3,4,5 |87| 96 tpi| | | ----------------------------------------------------------------------| Heath 89 |DSXD|40|4|15|0|18C|255| F0|0|64|2|1,2,3,4,5 |C7| 96 tpi| | | ----------------------------------------------------------------------| old |36| Heath 100|SSDD|32|3| 7|0| 97|127| F0|0|32|2|1,2,3,4,5,6,7,8 |82| ----------------------------------------------------------------------| old |36| Heath 100|DSDD|32|4|15|1| 9B|255| F0|0|64|2|1,2,3,4,5,6,7,8 |C6| ----------------------------------------------------------------------| old |SSDD| Heath 89 |SSSD|20|3| 7|0| 5B| 63| C0|0|16|3|1,2,3,4,5,6,7,8,9,10 |01| ----------------------------------------------------------------------| IBM CPM86|SSDD|32|3| 7|0| 9B| 63| C0|0|16|1|1,2,3,4,5,6,7,8 |82| ----------------------------------------------------------------------| Kaypro |SSSD|18|3| 7|0| 82| 31| 80|0|08|3|0,1,2,3,4,5,6,7,8,9 |02| ----------------------------------------------------------------------| Kaypro II|SSDD|40|3| 7|0| C2| 63| F0|0|16|1|1,6,11,16,3,8,13,18,5, |82| | |10,15,2,7,12,17,4,9,14 | | ----------------------------------------------------------------------| Kaypro4/10DSDD|40|4|15|1| C4| 63| C0|0|16|1|1,6,11,16,3,8,13,18,5, |E6| | |10,15,2,7,12,17,4,9,14 | | ----------------------------------------------------------------------| Kaypro DSQD|40|5|31|3| C4| 95| 80|0|18|2|1,6,11,16,3,8,13,18,5, |E6| | |10,15,2,7,12,17,4,9,14 | | ----------------------------------------------------------------------| Lobo Max80SSDD|36|3| 7|0| A5| 63| C0|0|16|3|0,1,2,3,4,5,6,7,8,9,10,|81| | |11,12,13,14,15,16,17 | | ----------------------------------------------------------------------| Lobo Max80DSDD|36|4|15|0| AC|127| C0|0|32|3|0,1,2,3,4,5,6,7,8,9,10,|C5| | |11,12,13,14,15,16,17 | | ----------------------------------------------------------------------| Morrow MD2SSDD|40|4|15|1| 5E|127| C0|0|32|2|1,4,2,5,3 |87| ----------------------------------------------------------------------| Morrow MD3DSDD|40|4|15|1| C2|191| E0|0|48|2|1,4,2,5,3 |C7| ----------------------------------------------------------------------| NEC PC8001A |32|3| 7|0| 97| 63| C0|0|16|2|1,2,3,4,5,6,7,8,9,10 |81| | |11,12,13,14,15,16 | | ----------------------------------------------------------------------| Osborne 2|SSDD|40|3| 7|0| B8| 63| C0|0|16|3|1,2,3,4,5 |83| ----------------------------------------------------------------------| Osborne 1|SSDD|20|4|15|1| 2D| 63| 80|0|16|3|1,3,5,7,9,2,4,6,8,10 |05| ----------------------------------------------------------------------| PMC-101 |DSDD|40|4|15|1| C2|127| C0|0|32|2|1,2,3,4,5 |C7| ----------------------------------------------------------------------| SANYO |DSDD|32|4|15|1| 9B| 63| 80|0|16|2|1,4,7,10,13,16,3,6,9, |C5| MBC 1000/1100 | |12,15,2,5,8,11,14 | | ----------------------------------------------------------------------| Telcon |DSDD|80|4|15|1| C2| 63| 80|0|16|1|1,2,3,4,5,6,7,8,9,10,11| | | |12,13,14,15,16,17,18,19,20| ----------------------------------------------------------------------| Telcon |DSXD|80|5|31|3| C4|127| 80|0|32|1|1,2,3,4,5,6,7,8,9,10,11| | 96 tpi| |12,13,14,15,16,17,18,19,20| ----------------------------------------------------------------------| Televideo|DSDD|36|4|15|0| AA| 63| 80|0|16|4|1,2,3,4,5,6,7,8,9,10, |C5| 802/803 | |11,12,13,14,15,16,17,18| | ----------------------------------------------------------------------| Televideo| |72|4|15|0| AA| 63| 80|0|16|2|1,2,3,4,5,6,7,8,9,10,11| | 820 | |12,13,14,15,16,17,18 | ----------------------------------------------------------------------| TIPro |SSDD|32|3| 7|0| 9B| 63| C0|0|16|1|1,2,3,4,5,6,7,8 |82| ----------------------------------------------------------------------| TRS80I OmiSSSD|18|3| 7|0| 52| 63| C0|0|16|3|1,5,9,13,17,3,7,11,15, |00| | |2,6,10,14,18,4,8,12,16 | | ----------------------------------------------------------------------| TRS80 III|SSDD|36|4|15|1| 54|127| C0|0|32|2|1,3,5,7,9,11,13,15,17, |81| Montezuma CPM | |2,4,6,8,10,12,14,16,18 | | ----------------------------------------------------------------------| TRS80 III|SSDD|40|4|15|1| 5E|127| C0|0|32|2|1,2,3,4,5,6,7,8,9,10 |86| w M.Merch. CPM| | | ----------------------------------------------------------------------| Xerox820I|SSSD|18|3| 7|0| 52| 31| 80|0| 8|3|1,6,11,16,3,8,13,18,5, |00| | |10,15,2,7,12,17,4,9,14 | | ----------------------------------------------------------------------| Xerox820IISSDD|34|3| 7|0| 9C| 63| C0|0|16|3|1,2,3,4,5,6,7,8,9,10,11|81| | |12,13,14,15,16,17,18 | | ======================================================================|