1581 Job Codes:
This table contains the addresses (logical Track and Sector, not physical!)
and the assigned buffers:
+-------+---------+----------+---------------+
| JOB | TRACK | SECTOR | BUFFER |
+-------+---------+----------+---------------+
| $02 | $0B | $0C | $0300-$03FF |
| $03 | $0D | $0E | $0400-$04FF |
| $04 | $0F | $10 | $0500-$05FF |
| $05 | $11 | $12 | $0600-$06FF |
| $06 | $13 | $14 | $0700-$07FF |
| $07 | $15 | $16 | $0800-$08FF |
| $08 | $17 | $18 | $0900-$09FF |
| $09 | $19 | $1A | $0A00-$0AFF |
| $0A | $1B | $1C | $0B00-$0BFF |
+-------+---------+----------+---------------+
If a disk controller routine is to be performed in the interrupt, one
writes the job code and the track and sector numbers of the block to be
processed (if necessary) in the appropriate memory locations. Now the
job code can be passed. This job code has a value greater than 127 (the
7th bit is set). In order to wait until the job is finished, only the
seventh bit need be tested. If this bit is cleared, the job is completed.
The disk controller can perform the following jobs:
+--------+--------------+-----------------------------------------------+
| Code | Name | Description |
+--------+--------------+-----------------------------------------------+
| $80 | READ_DV | Reads a particular logical sector into the |
| | | job queue buffer (only if the disk has not |
| | | been changed). If the desired sector is |
| | | already in the track cache buffer, then no |
| | | disk activity is required (the data is |
| | | merely transferred from the track cache |
| | | memory to the job queue buffer memory). If |
| | | the desired sector is not in the track |
| | | cache, then the current track cache is |
| | | dumped to disk (only if it has been |
| | | modified), the desired track is read into |
| | | the track cache, and finally the particular |
| | | sector's data is transferred from the track |
| | | cache memory to the job queue buffer. |
| | | |
| $82 | RESET_DV | Resets the disk controller and associated |
| | | variables. |
| | | |
| $84 | MOTON_DV | Turns on the spindle motor (overlays a $01 |
| | | in the Job Queue after the spin-up sequence |
| | | is complete). |
| | | |
| $86 | MOTOFF_DV | Turns the spindle motor off after the spin- |
| | | down sequence is complete. |
| | | |
| $88 | MOTONI_DV | Turns the spindle motor on immediately. |
| | | |
| $8A | MOTOFFI_DV | Turns the spindle motor off immediately. |
| | | |
| $8C | SEEK_DV | Seeks to a particular physical track |
| | | (cylinder). The current physical track |
| | | position should be put in the track |
| | | parameter of HDRS. |
| | | |
| $8E | FORMAT_DV | Formats one physical track (one half of a |
| | | cylinder). The head must be placed |
| | | physically over the proper cylinder, and |
| | | the head electronics must be selected for |
| | | the side desired. |
| | | |
| $90 | WRTSD_DV | Writes the job queue's buffer data to a |
| | | particular logical track, sector. If the |
| | | same track is already in the track cache, |
| | | then this involves only transferring the |
| | | job queue buffer data to the track cache |
| | | buffer. If a different track's data is in |
| | | the disk (only if it was modified), the |
| | | desired track read into the track cache |
| | | buffer, and finally the job queue buffer's |
| | | data transferred to the track cache. |
| | | |
| $92 | DISKIN_DV | Determines if there is a disk inserted in |
| | | the drive. |
| | | |
| $94 | LEDACTON_DV | Turns on the activity LED. |
| | | |
| $96 | LEDACTOFF_DV | Turns off the activity LED. |
| | | |
| $98 | ERRLEDON_DV | Enables error LED blinking. |
| | | |
| $9A | ERRLEDOFF_DV | Disables error LED blinking. |
| | | |
| $9C | SIDE_DV | Sets up the side select electronics to the |
| | | value specified (in SIDS). |
| | | |
| $9E | BUFMOVE_DV | Moves data between the job queue buffer and |
| | | the track cache buffer. The track parameter |
| | | in the job queue denotes the position in |
| | | the track cache buffer to transfer to/from. |
| | | The sector parameter denotes the following: |
| | | Bit 7 : Direction (1 = to track cache |
| | | buffer) |
| | | Bit 6 : Mark Flag (set/clear the 'track |
| | | cache modified' flag) |
| | | Bit 5 : Transfer (1 = do the transfer) |
| | | Bits 4-0:# of 256 byte blocks to transfer |
| | | With bit 7 set, the corresponding physical |
| | | track position in the job queue (HDRS2) |
| | | must be updated for the purpose of telling |
| | | the controller what physical track the |
| | | track cache buffer belongs to. In addition |
| | | the side var (SIDS) must also be updated. |
| | | |
| $A0 | WRTVER_DV | Verifies the track cache buffer's data |
| | | against the specified logical track's data. |
| | | |
| $A2 | TRKWRT_DV | Dumps the track cache buffer to the disk |
| | | (only if the track cache modified flag is |
| | | set). |
| | | |
| $A4 | SP_READ | Reads the specified physical sector |
| | | directly into RAM starting at #0 ($0300). |
| | | It does not use the track cache buffer. The |
| | | sector is always read from the disk |
| | | regardless of the current contents of the |
| | | track cache. |
| | | |
| $A6 | SP_WRITE | Writes to the specified physical sector |
| | | directly. It does not use the track cache. |
| | | Data to be written starts at buffer #0 |
| | | ($0300). |
| | | |
| $A8 | PSEEK_DV | Seeks to the specified physical track. |
| | | |
| $AA | TREAD_DV | Reads logical address without transferring |
| | | to the job queue buffer. |
| | | |
| $AC | TWRT_DV | Writes a logical address without |
| | | transferring from the job queue buffer. |
| | | |
| $B0 | SEEKHD_DV | Logs in a disk by reading information from |
| | | the first header encountered on the disk |
| | | into RAM so that it can be used by the DOS. |
| | | The track cache buffer is not updated. |
| | | |
| $B2 | TPREAD_DV | Reads a physical address without |
| | | transferring to the job queue buffer. |
| | | |
| $B4 | TPWRT_DV | Writes a physical address without |
| | | transferring from the job queue buffer. |
| | | |
| $B6 | DETWP_DV | Checks if the disk inserted is write |
| | | protected. Returns $00 if disk is not |
| | | protected, else $08. |
| | | |
| $B8 | SEEKPHD_DV | Seeks to a particular logical track, |
| | | sector. The track cache is not updated. |
| | | |
| $C0 | RESTORE_DV | Restores the read/write head to track 0 |
| | | ('bump'). |
| | | |
| $D0 | JUMPC_DV | Executes the code in the corresponding job |
| | | queue buffer. |
| | | |
| $E0 | EXBUF_DV | Executes the code in the corresponding job |
| | | queue buffer after the motor is up to speed |
| | | and the head is on track. |
| | | |
| $F0 | FORMATDK_DV | Formats the disk with the default physical |
| | | format. |
+--------+--------------+-----------------------------------------------+
If the job ends in an error then the memory location with job command
code is replaced with and error code. Here is a list of the error numbers:
+------+------------------+---------------------------------------------+
| Code | Name | Description |
+------+------------------+---------------------------------------------+
| $0x | OK_DV | No error. |
| $02 | MISHD_DV_ER | Can't find header block. |
| $03 | NOADAM_DV_ER | No address mark detected. |
| $04 | MISDBLK_DV_ER | Data block not present. |
| $05 | CRCDBLK_DV_ER | CRC error encountered in data block. |
| $06 | FMT_DV_ER | Format error. |
| $07 | VERERR_DV_ER | Verify error. |
| $08 | WRTPR_DV_ER | Attempt to write to a write protected disk. |
| $09 | CRCHD_DV_ER | CRC error encountered in header block. |
| $0A | | Reserved. |
| $0B | DSKCHG_DV_W | Disk was changed/disk ID mismatch. |
| $0C | DSKNTLOG_DV_ER | Disk format not logical. |
| $0D | CONTROLLER_DV_ER | Floppy disk controller IC error. |
| $0E | SYNTAX_DV_ER | Syntax error. Invalid job number. |
| $0F | NODSKPRS_DV_ER | No disk is present in the drive. |
+------+------------------+---------------------------------------------+
|