encoder loss bits

[bradp]

Hi, On acc24e2a with PowerPMAC at what addresses do we find the encoder loss bits?

[Sina.Sattari]

[quote='bradp' pid='494' dateline='1278536531'] Hi, On acc24e2a with PowerPMAC at what addresses do we find the encoder loss bits? [/quote] Brad, I think it would be bits 28 and 29 of the Gate3[].Chan[].Status word based upon the memory map included at the end of ACC-24E3 manual. Bit 28 is LossStatus which I believe changes and bit 29 latches if an encoder loss is detected. Also bit 30 gives the Count Error.

[bradp]

You think it is the same for Acc24e2a as it is for acc24e3 ?

[curtwilson]

On the ACC-24E2A, the encoder loss bits are found in the Lattice chip, not the ASIC, as in the ACC-24E3. Here are the base address offsets of the Lattice chips for each ACC-24E2x, given by the Gate1 index "i": 4: $D06040 6: $D06140 8: $D0E040 10: $D0E140 12: $D16040 14: $D16140 16: $D1E040 18: $D1E140 The 4 registers in the Lattice are at Base, Base+4, Base+8, and Base+$C, and the encoder loss bit is bit 13 on the 32-bit bus. So for the encoder-loss bit on the last channel of the first ACC-24E2A in a typical system (i=4), you could define: M400->u.io:$d0406C.13.1[hr] The table was half-wrong above. Correction and completion of the table of IC index numbers and ID chip base address offsets: 4: $D06040 5: $D06140 6: $D06050 7: $D06150 8: $D0E040 9: $D0E140 10: $D0E050 11: $D0E150 12: $D16040 13: $D16140 14: $D16050 15: $D16150 16: $D1E040 17: $D1E140 18: $D1E050 19: $D1E150