HP41CV with built-in Time Module

[wilbertschelvis]

Hi all,

I recently bought an HP41CV (Fullnut, #2121Sxxxxx) which seems to have a built-in Time Module. While there are no modules in the 4 slots, the Time Module functions show in the Catalog and they work OK. I cannot find anything about this in all the forums and websites that I know of.

Does anyone recognises this, have a similar HP41CV or maybe some further information?

Gr., Wilbert

[KeithB]

I assume you are sure it is not a CX. 8^)

I believe educalc had a service where they could mount modules internally, leaving the slots free.

[Mark H. Shin]

Could be that the original CV board was switched out with a CX board.

[brouhaha]

As others have noted, the electronics may not match the label.

If pressing [gold] CATALOG 4 shows the mainframe functions, just like CATALOG 3, then it really is a 41C or 41CV. If CATALOG 4 shows DIR EMPTY, or a listing of files in extended memory, then it's a 41CX.

Also, if CATALOG 2 includes "-TIME 2C", and includes "-CX TIME", "-EXT FCN 2D", and "-CX EXT FCN", then it's a 41CX.

If it's not a 41CX, but CATALOG 2 shows that it has another revision of the time module, then the time module has been installed internally. Sometimes such modification also include one or two Extended Memory modules, but usually not a Extended Function module, because that would conflict with an expansion port. With the ports empty, CATALOG 2 will tell you what other ROM modules may be installed, but it doesn't show extended memory modules.

If you can XEQ "EMDIR", that indicates that there IS an extended functions module installed (or in a port). if there's not one installed internally, plug one into a port and XEQ "EMDIR". It will probably say "DIR EMPTY", but when you hit the backarrow key, it will then show you how many registers of extended memory there are. If it's 124, that's just an extended function module, but if it's more, then there are one or two extended memory modules also.

[wilbertschelvis]

I checked, it is not a 41CX and it does not also contain any extended memory modules (checked with X-Memory module). Catalog 2 shows "-TIME- C". So it seems that a previous owner had the Time Module built-in.

Thanks for your replies.