Modem+KAY

Hello All! Please share the secrets of connecting a Hayes modem to a computer KAY-1024 according to the Kondratieff scheme. We connected the USRobotics 14400 modem according to the diagram for Scorpio and S-Terminal does not detect the modem, and Dickie hangs :(. SOS. SOS. What to do? There are symptoms. When starting any program that uses memory above 48k, vertical black and yellow stripes appear, and IS-DOS works normal, including electronic disk. We haven’t done anything with NMI yet, but connected it directly to the bus (signal B14). More Symptom: MAGIC does not work when the circuit is inserted. We tried another modem (Cirrus Logic 14400 voice) - the same symptoms :( Help whoever can. Don't let the realist remain without contact!!!!!!!!!!! Best regards, Stanislav.

Press RESET immediately, Stanislav! 06 Sep 00 21:20, Stanislav Udin wrote to All: SU> modem, and Dickie is hanging :(. SOS. SOS. What to do? There are symptoms. When SU> running any program that uses memory over 48k SU> vertical black and yellow stripes appear, and IS-DOS works SU> normal, including electronic disk. SU> We haven’t done anything with NMI yet, but connected it directly to the bus (signal B14). SU> Another symptom: MAGIC does not work when the circuit is inserted. SU> We tried another modem (Cirrus Logic 14400 voice) - the same symptoms SU> :( You have a port conflict there, that's for sure. And NMI had to be inverted (for example 155LA3) and connect through an open collector. In general, it is better not to connect the modem via NMI, it can simply lead to to unreliable computer operation. It's better to connect via INT. New version of Melon NAM can support such a scheme. For Dickie, only DosX needs to be redone. And it’s better to connect using the Kondratiev scheme with stricter decoding ports and using the IOGE signal <- mandatory! Moreover, the IOGE signal should be produced even before the IORQ signal appears on the processor, this can be doneeasy to do, because The processor sets the address half a clock cycle before the start of reading.

Greetings, Stanislav! [Wednesday September 6, 2000] at [21:20:42] Stanislav Udin wrote a letter to All. They discussed the topic "Modem+KAY". Let's continue what we started... SU> Please share the secrets of connecting a Hayes modem SU> to the KAY-1024 computer according to the Kondratieff scheme. We SU> connected the USRobotics 14400 modem according to the scheme for Scorpio and ^^^^^^^^^^^^^^^^ He needs -12V. Do we know? SU> S-Terminal does not detect the modem, and Dickie hangs :(. SOS. See below. They need interrupts (nmi). SU> SOS. What to do? There are symptoms. When starting any SU> programs that use memory over 48k appear SU> vertical black and yellow stripes, and IS-DOS works Most likely - above 128K, IMHO. SU> normal, including electronic disk. Something was tricky with decrypting the #ef port for the modem. Moreover, very strongly wise up. Or in Kay, the #ef port intersects with some other regular port. The meaning is: 1. Remove the modem from the slot. 2. In BASIC_128 we do: 10 FOR I=0 TO 255 20 OUT 239,I 30 NEXT I If your Kai specifically glitches after this, then we begin to actively implementmodem decryption circuit to generate a signal /IOGE. 3. In BASIC_128 we do: PRINT IN 239 If there is a value other than '255' (!) or the computer fails, then again we implement. SU> We haven't done anything with NMI yet, but connected it directly to the bus ^^^^^^^^^^^^^^^^^^^^^^^^^^^ See above. So only Melon will work for you. SU> (signal B14). What is this? Did you only apply /RD to the modem? What about B13? ;) SU> Another symptom: when the diagram is inserted, not SU> MAGIC works. The “magic” from the modem with the “magic” from Kai was incorrectly connected. Everything is mixed on one 2I valve (555LI1) and then fed to the 17th leg of the Z80. B The Scorp+Hayes scheme has this. I would not use the /nmi interception feature in Kai, but would put namely LI1. More reliable. SU> We tried another modem (Cirrus Logic 14400 voice) - the same SU> symptoms :( So it's not the modem. Modems are configured with jumpers as COM1/IRQ4??? Are the microcircuits for the mule (LH1, LL1, TM2) known to be good? ;) Best regards, Felix. [I.ZX] 27