Page Numbers: Yes X: 530 Y: 10.5"
Heading:

Alto-1822 Installation Notes

Filed on: [Ivy]<Alto-1822>Installation.note

Alto-1822 Installation Notes

This is a brief discussion of how to install an Alto-1822 interface.

Alto II

A standard Alto II has nearly all the required signals on slot 18. However, to install an Alto-1822 there, a few wires need to be added. If any of the J18 pins mentioned already have wires, stop and find out why!

Alto Signal NameFromTo1822 Signal Name
AUSYSCLKJ14-72J18-72AuSysClk
5ACT*J11-102J18-118ITAc’
TASKB*J10-14J18-117TASKB’
WAKE5*J11-60J18-112WakeIT’

Alto I

A standard Alto I has much less standard wiring. To install an Alto-1822 in slot 2, the following wires (at least) need to be added.

Alto Signal NameFromTo1822 Signal Name
AUSYSCLKJ7-72J2-72AuSysClk
-TASKBJ6-14J2-117TASKB’
-5ACTJ7-102J2-118ITAc’
-WAKE5J7-60J2-112WakeIT’
OKTORUNJ2-1J2-11OKToRun
-SIOJ3-41J2-41SIO’

In addition to the signals mentioned above, the following signals must be present at whatever slot you use:

BUS[00]-[15]
DBARC
F1[0]-[3]
F2[0]-[3]
NEXT[6]-[7]
OKTORUN
RESET

Cabling

The Alto-1822 internal cable is a 40 conductor ribbon cable with a 40 pin PC Card edge connector at the board end and a DB-37S connector at the Alto rear connector panel. Install it in the obvious way!

An Alto-1822 external cable is somewhat more complicated. Depending on the situation, it should be either a ’Local-Host’ cable or a ’Distant-Host’ cable. The former are for runs of up to about 30 feet, the latter for runs up to about 1000 feet. Refer to ’AICables.memo’ and BBN-1822 for additional information.