Cidco MailStation Mivo 100

model: DET1 aka MailStation 100 aka Mivo 100

cpu: Z80

RAM: 128 kByte SRAM

flash memory : 1MB (codeflash) and 512 kB (dataflash)

display: 320x128 monochrome LCD

modem: Rockwell RCV336DPFSP 33.6kbps modem with caller ID

parallel port: Bidirectional

real-time clock

keyboard: 72 keys

other: "new mail" LED

batteries: 3 x AA

power supply: 9 V DC , center pin negative


Cidco MailStation as a Z80 Development Platform, WiFiStation for Cidco MailStation, Fybertech MailStation Development, Wikipedia: Cidco MailStation,

more links

Github jcs/mailstation-tools, jcs/msTERM, cnvogelg/plipbox, garlick/pi-parport,

keys: Fn + Shift + T - diagnostic menu Shift + F5 (when in diag meny) - hex editor


Codeflash - The flash chip used to store the Mailstation OS.
Dataflash - The flash chip used to store user data
Slot4000  - The swappable 16KB section of address space between 0x4000 and 0x7FFF.
Slot8000  - The swappable 16KB section of address space between 0x8000 and 0xBFFF.
Device    - One of the pieces of hardware capable of being swapped into the slot4000 and slot8000 sections of address space.
Page      - A 16KB section of RAM, codeflash, or dataflash which can be switched into addressable space.


Codeflash - 29F080 1MB flash memory (64 pages)
Dataflash - 28SF040 512KB flash memory (32 pages)
RAM       - 128KB SRAM (8 pages)
LCD       - 320x128 monochrome display (two separate Mailstation devices, 160x128 each)
Modem     - Varies; sometimes RCV336ACFW 33.6kbps

address space layout

0x0000 - 0x3FFF: Always codeflash page 0
0x4000 - 0x7FFF: Variable device and page (slot4000)
0x8000 - 0xBFFF: Variable device and page (slot8000)
0xC000 - 0xFFFF: Always RAM page 0

The CPU (in everything but the Mailstation 350) is an 8-bit Z80-compatible, integrated into a custom ASIC.


2021-07-27: I discovered WiFiStation for Cidco MailStation by Joshua Stein. Cool stuff!

2021-06-24: I re-created this page on my self-hosted web server.

2019-05-28: I need a LapLink cable for transfer to the Mivo 100.

2019-05-27:power on test - first I tried with 3 old AA batteries, the Mivo 100 powerd on, but warned that the batteries were low and that it would automatically power off, which it did. With 3 fresh AA batteries, it works

2019-05-27: contents of package: one original box, with the following inside:

1 x Mivo 100 unit (white) in a insulated plastic bag
1 x power supply (Cidco Class 2 transformer, input 120VAC 60 Hz 9W, output 9VDC 500 mA 4.5VA, model no A30950) Note: this one has center negative
1 x MIVO 100 Quick Start Card
1 x sheet How To Activate Your service
1 x sheet "terms and conditions"
1 x User Manual, 52 pages

2019-05-21: at 15:10 received a pickup messages (email and text message), at 17:04 picked up the package at Extra Trondheimsveien on my way home.

2019-05-20: received tracking info from PostNord.

2019-05-12: my order was shipped.

2019-05-10: eBay - having read Cidco MailStation as a Z80 Development Platform and finding out that the Mivo 100 was available on eBay for ten dollars plus shipping, I couldn't resist, and ordered one. 1 x MailStation Mivo 100 - brand new for USD 9.99 + USD 7.51 in shipping and handling. A total of USD 17.50 or about NOK 160,36.