ETN #24

Engineering Technical Note

Microchip Technology, Inc. 03/11/2002 Page 1 of 1

Timer1 Oscillator Support Issue Problem: Hardware design issue supporting timer1 oscillator input with the following Device Adapters: DVA16XP282 (02-01483 Rev. 6 or earlier) DVA16XP401 (02-01447 Rev. 5 or earlier) DVA16XL441 (02-01515 Rev. 4 or earlier) DVA16PQ441 (02-01516 Rev. 3 or earlier) The above device adapter designs routes the timer1 OSC-ME clock on the device adapter to RC1/T1OSI of the Processor Modules –ME, however, the timer1 OSC-ME clock should be routed to RC0/T1OSO/T1CKI of the Processor Modules –ME. The table below shows which Processor Modules require an updated Device Adapter for supporting timer1 oscillator.

Processor Module Original Device Adapters Acceptable

Updated Device Adapters Required

PCM16XB0/B1 (C74A) Yes PCM16XD0 (C662) N/A (see below) N/A (see below) PCM16XE0/E1 (C77) Yes PCM16XK0/K1 (F877) Yes PCM16XL0 (C774) Yes PCM16XQ0 (C765) Yes PCM16XR0/R1 (F872) Yes PCM16XS0/S1 (F77) Yes PCM18XA0 (C452) Yes PCM18XC0/C1 (F452) Yes PCM18XD0/D1 (F458) Yes

Note: PIC16C64X/66X Family does not support Timer1 Solution: Update Device Adapter PCB designs to route the Timer1 OSC-ME clock to RC0/T1OSO/T1CKI of the Processor Module. The new design will be backward compatible with all Processor Modules supporting these Device Adapters.