E-prom Replacement Procedure for the MIP-921

1.  Disconnect power to the MIP-921 by unplugging the power cube from the outlet and then removing the 1/8" power plug from the back of the unit.

2.  Remove the 4 screws from the top cover and remove the cover.

3.  Locate U3, the 28 PIN E-prom IC to be changed.  The location of this IC on your MIP-921 may be in 1 of 2 places.  First look directly behind the 4 front panel LED's.  Note the printing on the circuit board indicating the identity of the first IC behind the 4 front LED's.  If the identifier is U3, please follow Explanation A.  If the identifier shows U4, follow Explanation B.  

Explanation A

If you have an IC pry tool, use it to remove U3.  If no IC pry tool is available, a jewelers straight slot screwdriver would be recommended.  Making sure that you are prying the IC and not the IC socket, gently pry first on the left and then on the right until the IC is removed.  Insert your new E-prom into the socket noting that the dimple on the IC is located on the same side as the dimple on the socket.   (The dimple should be on the left hand side of the IC socket as you are facing the unit).  IMPORTANT:  Reconnect the 1/8" power plug into the back of the unit and then plug in the power cube into the outlet, noting the LCD will read "MIP-921 Ready".  The "Ready" Front Panel LED will be illuminated. 

If you plug the unit in and "MIP-921 Ready" does not appear in the LCD, check the replacement E-prom for proper orientation.  If the LCD shows "Start Up Error", see Default Restart below. 

Explanation B

Remove "F" connector nuts from the 3 ports on the rear of the unit.  Locate P1 connector on the MIPRF circuit board and remove it from the circuit board by pulling upward on the connector.  Remove 3 Phillips screws from the back of the MIP-921 and remove the shelf and circuit boards from the MIP-921 unit.   On the circuit board remaining in the MIP, locate U3 which is positioned beside U4.   (The Lithium Time Keeper Battery). 

If you have an IC pry tool use it to remove U3.  If no IC pry tool is available, a jewelers straight slot screwdriver would be recommended.  Making sure that you are prying the IC and not the IC socket, gently pry first on the left and then on the right until the IC is removed.  Insert your new E-prom into the socket noting that the dimple on the IC is located on the same side as the dimple on the socket.   (The dimple should be on the left hand side of the IC socket as you are facing the unit). 

Reinstall the shelf and circuit board assembly.  Put the "F" connector nuts back on ports.  Be sure to reconnect P1 to the circuit board. 

Reconnect the 1/8" power plug into the back of the unit and then plug the power cube into the outlet, noting the LCD will read "MIP-921 Ready".  The "Ready" Front Panel LED will be illuminated.  

Default Restart

If you plug the unit in and "MIP-921 Ready" does not appear in the LCD, check the replacement E-prom for proper orientation.  If the LCD shows "Start Up Error" you will need to perform a default restart.  This default restart will reset the MIP with a preprogrammed list of counties and events.  (NOTE:   This will clear all of the counties and events previously programmed by the user.)   IMPORTANT:  To initiate the default start up, begin by unplugging the power cube from the outlet.  Then remove the 1/8" power plug on the back of the MIP.  Wait 10 seconds, then while depressing the ENTER key on the front panel, re-power the unit by reinserting the 1/8" power plug on the back of the MIP and then plugging the power cube into the outlet.  You should now reprogram your MIP according to your specific needs. 

NOTE:  Please place the old chip in the plastic cover and place it in the envelope in which you received the new E-prom and return to the HollyAnne Corporation.