The Sinclair QL Forum

Hi James - you're very welcome. OK, one more question - when you test that voltage at Pin 10 of slot#2, was that with/without an MDV unit connected in slot#1, or either way? Some other useful check-point suggestions for when you find the time: a) What voltage is present at Pin 2 (COMMS OUT) of slot#...

Hi James! I've been thinking about your 'leaky' MDV 2 and taking another look at the schematic, I'm wondering about the possibility of leakage from the MDRW line that - on QL MDVs - is connected via D23 (and D22 for MDV 1) though the WP switch in a 'clever' arrangement to enforce write-protection. T...

That'd be great, Peter :-) IIRC, when I was still debugging the Q68-ND driver, I measured each access-cycle to the I/O area at around 1uS - in any case, I had to be cautious in writing the debug byte out to the port during time-critical parts of the ND driver code as it soon started to skew the deli...

Hi Derek

I concur with the male-header approach - I have made such mods to my two Q68s in order to tap-off QLNET (as well as adding a 'debug' port during development of the ND-Q68 driver.)

M.

Hi! VP makes a good point that I hadn't considered. Have you configured the picoUSB to drive 9V in to the respective Vin connector on the motherboard, or instead 5V directly in to where the output from the main 5V linear regulator feeds the board? If the former, then aside from any residual damage f...

Hi Stephen Wow - you showed great determination! Your little problem has set me thinking about the whole Spectrum 'fileserver' thing... I've got some ideas that I'll put in to action in a little while. Until I can crack the NET reliability issue between a BBQL and the Spectrum, any success will rely...

Hi Tom Whilst there may be other problems (the programming of the GALs for one), it seems to me from your photo that the resistor array may be fitted back-to-front. Pin 1 of the array is typically the 'common' pin and marked with the white 'dot', should be connected to Vcc and marked on the PCB adja...

Hi Stephen! Your current requirement poses a very interesting use-case that I have been investigating myself as a spin-off from my on-going research in to the QL NET capability. To add to what has already been suggested, here are some thoughts to get you moving... The fundamental issues to be addres...

Hi Andrew The underlying QDOS 'FSTRG' TRAP is designed the way you need - reading bytes from a channel, directly in to a bounded memory buffer. To access this IO Trap From SBasic, you could use DIYTK's 'QTRAP' extension (Volume T), providing '3' for the TRAP ID/Operation Key, thus: QTRAP #<input_cha...

Well done for persevering, Bill! Out of interest, which OS were you running when trying to format the MDV image? QDOS and Minerva have different 'tolerances' as to what constitutes a reliable result from the FORMAT command and vDrive has been configured to report a suitable number of sectors so as t...