jkg@gitpyr.UUCP (04/24/87)
In article <1149@botter.cs.vu.nl> ast@cs.vu.nl (Andy Tanenbaum) writes: >1. The IBM PC-AT (old 6 MHz machine) has no brand name or model number on > the card. It does have the following 3 chips though: > WD1010P1-05 > WD1014CL-01 > WD1015PL-03 >If we have any experts in reading chip entrails out there, please speak up. Well, I don't know if I'm an expert, but I do have a Western Digital data book :-). Here's the dirt on the above chips: WD1010P1-05 is a Winchester disk controller designed to be used with ST506 and SA1000 interfaces. It supports sector sizes of 128, 256, 512, and 1024 bytes. It reads and writes MFM-encoded data and computes a CRC automatically using the polynomial X^16+X^12+X^5+1. It supports up to 4 drives and up to 8 heads. It also supports the primitives RESTORE, SEEK, READ SECTOR, WRITE SECTOR, SCAN ID, and WRITE FORMAT. The RESTORE and SEEK commands allow 16 possible step rates from 35 usec up to 7.5 msec in increments of 0.5 msec. The FORMAT command allows automatic marking of bad blocks and permits any physical/logical mapping desired, thereby allowing the interleave factor to be fully user-programmable. According to the data sheet, Western Digital WD1000 controller boards are software compatible with the WD1010-05. WD1014CL-01 is an error detection device which computes a 32 bit ECC using the forward polynomial X^32+X^28+X^26+X^19+X^17+X^10+X^6+X^2+1. The reverse polynomial is X^32+X^30+X^26+X^22+X^15+X^13+X^6+X^4+1. It supports the same sector sizes as the WD1010-05. When used in conjunction with the WD1010-05, then the WD1010-05 must be programmed to read the additional error detection data provided by the WD1014-01. In this instance, the CRC is not appended to the data field by the WD1010-05, but it is still computed. Both devices support data rates of 5 Mbits/sec. WD1015PL-03 is a buffer manager chip. Unfortunately, I can't provide a whole lot of information about this one because my data book (dated June, 1984) lists it as "Advance Information". Basically all I have is a pin-out and description of the signals. Apparently, the WD1015 is the "brains" of the chip-set and monitors activity on the data bus and coordinates the actions of the WD1010-05, WD1014, and the host processor. I do, however, have a data sheet for the WD1002-05 Winchester/Floppy Con- troller. It uses this same chip-set, along with a WD2797 floppy disk controller. I also have a data sheet for the WD1002-WX2, which claims to emulate an IBM XT Winchester controller, and has an IBM PC bus interface. It uses the WD1010-05 and WD1015, but not the WD1014. Instead, a WD1100-13 error detection device is used. It uses the same polynomial as the WD1014, but gets polynomial data via an 8-bit parallel bus (the WD1014 is a 2-bit serial device). Since I have a vested interest in getting MINIX up and running on a hard disk (I have an AT&T PC 6300 with 1 floppy and 1 hard disk), I will be more than happy to answer SPECIFIC questions about device operation from the data sheets. Obviously, I can't answer questions relating to PC specific stuff since that info is not available from the data book. I think the information might be useful to some folks, though. Opinions, anyone? Jim Greenlee -- The Shadow...!{akgua,allegra,amd,hplabs,ihnp4,seismo,ut-ngp}!gatech!gitpyr!jkg Jryy, abj lbh'ir tbar naq qbar vg! Whfg unq gb xrrc svqqyvat jvgu vg hagvy lbh oebxr vg, qvqa'g lbh?!