Dear CUSTOMER,
Complete ATARI ST/F/M upgrade consists of two boards: HEREON itself and dedicated adapter for Your ATARI ST motherboard
Please, read carefully desrciption below
ATARI ST 4MB expansion
- Designed by Bartek Swiderski.
- produced at smd.lotharek.pl
- set consists of 2 pcbs sold separatelly
- HERON itself
- dedicated adapter (please, read below)
HERON RAM Upgrade expansion board is 16 MB RAM module for Atari ST. Due to the hardware limitation of the memory management system offered by the original MMU chip, STARI ST can only use 4 MB, however after replacing the MMU with RemakeMMU (in development) one will have 10 MB (MEGA ST) or even 14 MB (future plans).
Compatibility
- The extension is compatible with all Atari ST/STF/STFM and MEGA ST.
Disclaimer:
- THERE IS DANGEROUS VOLTAGE AC inside ATARI - disconnect power supply first !
- If you are not familiar with soldering or you do not have proper tools, please LET a pro technician do it for you
- Please remeber - wrong tools usage or low skills may damage atari and Heron
- Any damage/harm to your hardware is NOT subject of any kind of warranty.
- Installation is easy, but unexperienced hands can do a lot of damage.
- I assume You can disassemble Your atari ST, so no detailed instructions or safety precautions here.
- You know what You are doing !!!
- You know how multemeter works !!!
- You have read FAQ tab above !!
STEP BY STEP:
- buy at least 2 beers :-) and turn off internet ! no need to send me mails with question, how to proceed ;-)
- install HERON in place of shifer chip - be carefull with orientation! notch to notch - CLICK ME !
- If it is socketed - it will take you 20seconds, if not - much longer :-)
- put the shifter back into HERON
- install dedicated resistor pack in its place; please refer to resistor_pack manual - links below
- disable old rams - please, refer to FAQ tab
- connect HERON and RESISTOR_PACK pcb with zif cable
- solder a wire to connect A9 from MMU to resistor pack
- solder a wire to connect WE signal from old memory chips to resistor pack
- ready :-). You have 4MB of RAM :-)
bottom of pcb - MMU CHIP and A9 signal / motherboards with MMU socketedt/
Inside box:
- fully tested and assembled HERON board
Selection of extension borad
- The simplest installation /and only one supported/ is possible with the COMPLETE SET : HERON + replacement board equipped with anti-kickback resistors
- Unfortunatelly, there is no universal solution. Atari ST computers were produced by many factories for a long time, so there are many versions of the board.
- Each version has a unique marking on the motherboard as in the photo below.
Available adapters:
Product gallery
Q. Extension/ Heron doesnt work... what have i done wrong ?
99% of problems is caused by NOT DISABLING old ram with PULLING HIGH RAS signal of OLD MEMORY CHIPS.
You do remeber, You cut out RAS resistor? it means You have disconnected controlling signal wire from MMU chip to ram present at Your board...
....But old old rams are stilll active, waiting for RAS. You must supply them signal saying: shut up, go to sleep ;-) - otherwise old ram will be bouncing around data lines ;-)
follow manual ...or below picture, saying: 1 piece of resistor for each 512kB... or REMOVE OLD RAM CHIPS :-)
whatever You do, this part is VITAL for HERON TO WORK:
OLD RAM MUST BE DISABLED somehow...
Another problem: ZIF CONNECTORS are BOTTOM CONTACT. You must see BLUE piece on top.
Another problem...is SHITHAPPENS MISTAKES:
- if you look closer, you will see sth may be NOK.. SHORTUCT between WE signal and righ side of resistor under the pcb !
- did You read previous remark about blue indicators at zif cables ? below cables are inserted upside down :-)
- ONE RESISTOR for ONE 512kb BANK as each bank has its own RAS SIGNAL
- Thank You Tomasz for support and showing impossible for me is possible :-)
simple checks with multimeter in "beep mode"
- probe pins 3 and 4 ( WE and RAS) at any old memory chip- shall no BEEP !
simple checks with multimeter in "VCC mode"
- measure betwen pin 16 and 3 ( GND and RAS) at any memory chip - 5V shall be present
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